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Chapter 3 Building Planning

Section R301 Design Criteria

R301.1 Application

Buildings and structures, and parts thereof, shall be constructed to safely support all loads, including dead loads, live loads, roof loads, flood loads, snow loads, wind loads and seismic loads as prescribed by this code. The construction of buildings and structures in accordance with the provisions of this code shall result in a system that provides a complete load path that meets the requirements for the transfer of loads from their point of origin through the load-resisting elements to the foundation. Buildings and structures constructed as prescribed by this code are deemed to comply with the requirements of this section.
Exception: Buildings and structures located within the High Velocity Hurricane Zone shall comply with Sections R302 to R328, inclusive and the provisions of Chapter 44, Sections R301.2.5 and R406. In addition, buildings and structures located in flood hazard areas established in Table R301.2(1) shall comply with Sections R301.2.4, R301.2.5 and R322.

R301.1.1 Alternative Provisions

As an alternative to the requirements in Section R301.1, the following standards are permitted subject to the limitations of this code and the limitations therein. Where engineered design is used in conjunction with these standards, the design shall comply with the Florida Building Code, Building.
  1. AF&PA Wood Frame Construction Manual (WFCM).
  2. AISI Standard for Cold-Formed Steel Framing—Prescriptive Method for One- and Two-Family Dwellings (AISI S230).
  3. ICC Standard on the Design and Construction of Log Structures (ICC 400).

R301.1.2 Construction Systems

The requirements of this code are based on platform and balloon-frame construction for light-frame buildings. The requirements for concrete and masonry buildings are based on a balloon framing system. Other framing systems must have equivalent detailing to ensure force transfer, continuity and compatible deformations.

R301.1.3 Engineered Design

Where a building of otherwise conventional construction contains structural elements exceeding the limits of Section R301 or otherwise not conforming to this code, these elements shall be designed in accordance with accepted engineering practice. The extent of such design need only demonstrate compliance of nonconventional elements with other applicable provisions and shall be compatible with the performance of the conventional framed system. Engineered design in accordance with the Florida Building Code, Building is permitted for buildings and structures, and parts thereof, included in the scope of this code.

R301.2 Climatic and Geographic Design Criteria

Buildings shall be constructed in accordance with the provisions of this code as limited by the provisions of this section. Additional criteria shall be set forth in Table R301.2(1).
TABLE R301.2(1)
CLIMATIC AND GEOGRAPHIC DESIGN CRITERIA
GROUND
SNOW
LOAD		 WIND DESIGN SEISMIC
DESIGN
CATEGORYf		 SUBJECT TO DAMAGE FROM WINTER
DESIGN
TEMPe		 ICE BARRIER REQUIREDh FLOOD
HAZARDSg
 AIR
FREEZING
INDEXi		 MEAN
ANNUAL
TEMPj
Speedd
(mph)
 Topographic
effectsk
 Special wind
regionl
 Wind-borne
debris zonem
 Weatheringa Frost line
depthb
 Termitec
NA See Fig. R301.2(4) NA Negligible NA Very Heavy NA NA NA
For SI: 1 pound per square foot = 0.0479 kPa, 1 mile per hour = 0.447 m/s.
  1. Weathering may require a higher strength concrete or grade of masonry than necessary to satisfy the structural requirements of this code. The weathering column shall be filled in with the weathering index, "negligible," "moderate" or "severe" for concrete as determined from Figure R301.2(3). The grade of masonry units shall be determined from ASTM C34, C55, C62, C73, C90, C129, C145, C216 or C652.
  2. Reserved.
  3. Termite infestation per Figure R301.2(6) is "very heavy."
  4. Wind speed shall be from the basic wind speed map [Figure R301.2(4)]. Wind exposure category shall be determined on a site-specific basis in accordance with Section R301.2.1.4.
  5. The outdoor design dry-bulb temperature shall be selected from the columns of 971/2-percent values for winter from Appendix D of the Florida Building Code, Plumbing. Deviations from the Appendix D temperatures shall be permitted to reflect local climates or local weather experience as determined by the building official.
  6. Reserved.
  7. The applicable governing body shall, by local floodplain management ordinance, specify (a) the date of the jurisdiction's entry into the National Flood Insurance Program (date of adoption of the first code or ordinance for management of flood hazard areas), (b) the date(s) of the Flood Insurance Study and (c) the panel numbers and dates of the currently effective FIRMs and FBFMs or other flood hazard map adopted by the authority having jurisdiction, as amended.
  8. Reserved.
  9. Reserved.
  10. Reserved.
  11. Reserved.
  12. Reserved.
  13. Reserved.
TABLE R301.2(2)
COMPONENT AND CLADDING LOADS FOR A BUILDING WITH A MEAN ROOF HEIGHT OF 30 FEET LOCATED IN EXPOSURE B (ASD) (psf)a, b, c, d, e, f
ZONE EFFECTIVE
WIND AREA
(ft2)		 ULTIMATE DESIGN WIND SPEED, VULT (mph)
115 120 130 140 150 160 170 180
Pos Neg Pos Neg Pos Neg Pos Neg Pos Neg Pos Neg Pos Neg Pos Neg
Gable Roof 0 to 7 degrees 1, 1'g 10 10.0 -22.7 10.0 -24.8 10.0 -29.1 10.0 -33.7 10.0 -38.7 11.2 -44.0 12.7 -49.7 14.2 -55.7
1, 1'g 20 10.0 -20.2 10.0 -22.0 10.0 -25.8 10.0 -29.9 10.0 -34.4 10.5 -39.1 11.9 -44.1 13.3 -49.5
1, 1'g 50 10.0 -16.8 10.0 -18.3 10.0 -21.5 10.0 -24.9 10.0 -28.6 -29.9 -32.5 10.8 -36.7 12.2 -41.2
1, 1'g 100 10.0 -14.3 10.0 -15.5 10.0 -18.2 10.0 -21.2 10.0 -24.3 -29.9 -27.6 10.0 -31.2 11.3 -35.0
2 10 10.0 -30.0 10.0 -32.7 10.0 -38.3 10.0 -44.5 10.0 -51.0 11.2 -58.1 12.7 -65.6 14.2 -73.5
2 20 10.0 -26.7 10.0 -29.1 10.0 -34.2 10.0 -39.6 10.0 -45.5 10.5 -51.8 11.9 -58.4 13.3 -65.5
2 50 10.0 -22.4 10.0 -24.4 10.0 -28.6 10.0 -33.2 10.0 -38.1 -29.9 -43.3 10.8 -48.9 12.2 -54.8
2 100 10.0 -19.1 10.0 -20.8 10.0 -24.4 10.0 -28.3 10.0 -32.5 10.0 -37.0 10.0 -41.8 11.3 -46.8
3 10 10.0 -40.9 10.0 -44.5 10.0 -52.2 10.0 -60.6 10.0 -69.6 11.2 -79.1 12.7 -89.4 14.2 -100.2
3 20 10.0 -34.4 10.0 -37.4 10.0 -43.9 10.0 -50.9 10.0 -58.4 10.5 -66.5 11.9 -75.1 13.3 -84.2
3 50 10.0 -25.6 10.0 -27.9 10.0 -32.8 10.0 -38.0 10.0 -43.6 10.0 -49.6 10.8 -56.0 12.2 -62.8
3 100 10.0 -19.1 10.0 -20.8 10.0 -24.4 10.0 -28.3 10.0 -32.5 10.0 -37.0 10.0 -41.8 11.3 -46.8
Gable Roof > 7 to 20 degrees 1, 2e 10 10.6 -26.4 11.6 -28.7 13.6 -33.7 15.8 -39.1 18.1 -44.9 20.6 -51.0 23.3 -57.6 26.1 -64.6
1, 2e 20 10.0 -26.4 10.0 -28.7 11.7 -33.7 13.6 -39.1 15.6 -44.9 17.8 -51.0 20.1 -57.6 22.5 -64.6
1, 2e 50 10.0 -16.1 10.0 -17.5 10.0 -20.6 10.8 -23.8 12.3 -27.4 14.0 -31.1 15.9 -35.2 17.8 -39.4
1, 2e 100 10.0 -8.2 10.0 -9.0 10.0 -10.5 10.0 -12.2 10.0 -14.0 11.2 -15.9 12.7 -18.0 14.2 -20.2
2n, 2r, 3e 10 10.6 -38.5 11.6 -41.9 13.6 -49.2 15.8 -57.0 18.1 -65.4 20.6 -74.5 23.3 -84.1 26.1 -94.2
2n, 2r, 3e 20 10.0 -33.2 10.0 -36.2 11.7 -42.4 13.6 -49.2 15.6 -56.5 17.8 -64.3 20.1 -72.6 22.5 -81.4
2n, 2r, 3e 50 10.0 -26.2 10.0 -28.5 10.0 -33.5 10.8 -38.8 12.3 -44.6 14.0 -50.7 15.9 -57.2 17.8 -64.2
2n, 2r, 3e 100 10.0 -20.9 10.0 -22.8 10.0 -26.7 10.0 -31.0 10.0 -35.6 11.2 -40.5 12.7 -45.7 14.2 -51.3
3r 10 10.6 -45.7 11.6 -49.8 13.6 -58.4 15.8 -67.8 18.1 -77.8 20.6 -88.5 23.3 -99.9 26.1 -112.0
3r 20 10.0 -39.2 10.0 -42.7 11.7 -50.1 13.6 -58.1 15.6 -66.7 17.8 -75.9 20.1 -85.6 22.5 -96.0
3r 50 10.0 -30.5 10.0 -33.2 10.0 -39.0 10.8 -45.2 12.3 -51.9 14.0 -59.0 15.9 -66.6 17.8 -74.7
3r 100 10.0 -24.0 10.0 -26.1 10.0 -30.6 10.0 -35.5 10.0 -40.8 11.2 -46.4 12.7 -52.3 14.2 -58.7
Gable Roof > 20 to 27 degrees 1, 2e 10 10.6 -20.3 11.6 -22.1 13.6 -26.0 15.8 -30.1 18.1 -34.6 20.6 -39.3 23.3 -44.4 26.1 -49.8
1, 2e 20 10.0 -20.3 10.0 -22.1 11.7 -26.0 13.6 -30.1 15.6 -34.6 17.8 -39.3 20.1 -44.4 22.5 -49.8
1, 2e 50 10.0 -17.3 10.0 -18.8 10.0 -22.1 10.8 -25.6 12.3 -29.4 14.0 -33.5 15.9 -37.8 17.8 -42.4
1, 2e 100 10.0 -14.9 10.0 -16.2 10.0 -19.0 10.0 -22.1 10.0 -25.3 11.2 -28.8 12.7 -32.5 14.2 -36.5
2n, 2r, 3e 10 10.6 -32.4 11.6 -35.3 13.6 -41.4 15.8 -48.0 18.1 -55.2 20.6 -62.8 23.3 -70.8 26.1 -79.4
2n, 2r, 3e 20 10.0 -28.4 10.0 -31.0 11.7 -36.3 13.6 -42.1 15.6 -48.4 17.8 -55.0 20.1 -62.1 22.5 -69.6
2n, 2r, 3e 50 10.0 -23.1 10.0 -25.2 10.0 -29.5 10.8 -34.2 12.3 -39.3 14.0 -44.7 15.9 -50.5 17.8 -56.6
2n, 2r, 3e 100 10.0 -19.1 10.0 -20.8 10.0 -24.4 10.0 -28.3 10.0 -32.5 11.2 -37.0 12.7 -41.8 14.2 -46.8
3r 10 10.6 -38.5 11.6 -41.9 13.6 -49.2 15.8 -57.0 18.1 -65.4 20.6 -74.5 23.3 -84.1 26.1 -94.2
3r 20 10.0 -32.4 10.0 -35.3 11.7 -41.4 13.6 -48.0 15.6 -55.2 17.8 -62.8 20.1 -70.8 22.5 -79.4
3r 50 10.0 -24.0 10.0 -26.1 10.0 -30.6 10.8 -35.5 12.3 -40.8 14.0 -46.4 15.9 -52.3 17.8 -58.7
3r 100 10.0 -24.0 10.0 -26.1 10.0 -30.6 10.0 -35.5 10.0 -40.8 11.2 -46.4 12.7 -52.3 14.2 -58.7
Gable Roof > 27 to 45 degrees 1, 2e, 2r 10 13.1 -24.0 14.2 -26.1 16.7 -30.6 19.4 -35.5 22.2 -40.8 25.3 -46.4 28.5 -52.3 32.0 -58.7
1, 2e, 2r 20 11.6 -20.3 12.6 -22.1 14.8 -26.0 17.2 -30.1 19.8 -34.6 22.5 -39.3 25.4 -44.4 28.5 -49.8
1, 2e, 2r 50 10.0 -15.5 10.5 -16.9 12.4 -19.8 14.3 -22.9 16.5 -26.3 18.7 -30.0 21.1 -33.8 23.7 -37.9
1, 2e, 2r 100 10.0 -11.9 10.0 -12.9 10.5 -15.1 12.2 -17.6 14.0 -20.2 15.9 -22.9 18.0 -25.9 20.2 -29.0
2n, 3r 10 13.1 -26.4 14.2 -28.7 16.7 -33.7 19.4 -39.1 22.2 -44.9 25.3 -51.0 28.5 -57.6 32.0 -64.6
2n, 3r 20 11.6 -23.6 12.6 -25.7 14.8 -30.1 17.2 -34.9 19.8 -40.1 22.5 -45.6 25.4 -51.5 28.5 -57.8
2n, 3r 50 10.0 -19.9 10.5 -21.6 12.4 -25.4 14.3 -29.4 16.5 -33.8 18.7 -38.4 21.1 -43.4 23.7 -48.6
2n, 3r 100 10.0 -17.1 10.0 -18.6 10.5 -21.8 12.2 -25.3 14.0 -29.0 15.9 -33.0 18.0 -37.3 20.2 -41.8
3e 10 13.1 -32.4 14.2 -35.3 16.7 -41.4 19.4 -48.0 22.2 -55.2 25.3 -62.8 28.5 -70.8 32.0 -79.4
3e 20 11.6 -28.8 12.6 -31.3 14.8 -36.8 17.2 -42.7 19.8 -49.0 22.5 -55.7 25.4 -62.9 28.5 -70.5
3e 50 10.0 -24.0 10.5 -26.1 12.4 -30.6 14.3 -35.5 16.5 -40.8 18.7 -46.4 21.1 -52.3 23.7 -58.7
3e 100 10.0 -20.3 10.0 -22.1 10.5 -26.0 12.2 -30.1 14.0 -34.6 15.9 -39.3 18.0 -44.4 20.2 -49.8
Hip Roof 7 to 20 degreesh 1 10 10.6 -24.0 11.6 -26.1 13.6 -30.6 15.8 -35.5 18.1 -40.8 20.6 -46.4 23.3 -52.3 26.1 -58.7
1 20 10.0 -24.0 10.0 -26.1 11.7 -30.6 13.6 -35.5 15.6 -40.8 17.8 -46.4 20.1 -52.3 22.5 -58.7
1 50 10.0 -18.5 10.0 -20.2 10.0 -23.7 10.8 -27.4 12.3 -31.5 14.0 -35.8 15.9 -40.4 17.8 -45.3
1 100 10.0 -14.3 10.0 -15.5 10.0 -18.2 10.0 -21.2 10.0 -24.3 11.2 -27.6 12.7 -31.2 14.2 -35.0
2r 10 10.6 -31.2 11.6 -34.0 13.6 -39.9 15.8 -46.3 18.1 -53.1 20.6 -60.4 23.3 -68.2 26.1 -76.5
2r 20 10.0 -28.1 10.0 -30.6 11.7 -35.9 13.6 -41.7 15.6 -47.9 17.8 -54.4 20.1 -61.5 22.5 -68.9
2r 50 10.0 -24.0 10.0 -26.1 10.0 -30.7 10.8 -35.6 12.3 -40.9 14.0 -46.5 15.9 -52.5 17.8 -58.8
2r 100 10.0 -20.9 10.0 -22.8 10.0 -26.7 10.0 -31.0 10.0 -35.6 11.2 -40.5 12.7 -45.7 14.2 -51.3
2e, 3 10 10.6 -33.6 11.6 -36.6 13.6 -43.0 15.8 -49.8 18.1 -57.2 20.6 -65.1 23.3 -73.5 26.1 -82.4
2e, 3 20 10.0 -30.3 10.0 -32.9 11.7 -38.7 13.6 -44.8 15.6 -51.5 17.8 -58.6 20.1 -66.1 22.5 -74.1
2e, 3 50 10.0 -25.8 10.0 -28.0 10.0 -32.9 10.8 -38.2 12.3 -43.8 14.0 -49.9 15.9 -56.3 17.8 -63.1
2e, 3 100 10.0 -22.4 10.0 -24.4 10.0 -28.6 10.0 -33.2 10.0 -38.1 11.2 -43.3 12.7 -48.9 14.2 -54.8
Hip Roof > 20 to 27 degrees 1 10 10.6 -19.1 11.6 -20.8 13.6 -24.4 15.8 -28.3 18.1 -32.5 20.6 -37.0 23.3 -41.8 26.1 -46.8
1 20 10.0 -16.9 10.0 -18.4 11.7 -21.6 13.6 -25.1 15.6 -28.8 17.8 -32.8 20.1 -37.0 22.5 -41.5
1 50 10.0 -14.0 10.0 -15.3 10.0 -17.9 10.8 -20.8 12.3 -23.9 14.0 -27.2 15.9 -30.7 17.8 -34.4
1 100 10.0 -11.9 10.0 -12.9 10.0 -15.1 10.0 -17.6 10.0 -20.2 11.2 -22.9 12.7 -25.9 14.2 -29.0
2e, 2r, 3 10 10.6 -26.4 11.6 -28.7 13.6 -33.7 15.8 -39.1 18.1 -44.9 20.6 -51.0 23.3 -57.6 26.1 -64.6
2e, 2r, 3 20 10.0 -23.6 10.0 -25.7 11.7 -30.1 13.6 -34.9 15.6 -40.1 17.8 -45.6 20.1 -51.5 22.5 -57.8
2e, 2r, 3 50 10.0 -19.9 10.0 -21.6 10.0 -25.4 10.8 -29.4 12.3 -33.8 14.0 -38.4 15.9 -43.4 17.8 -48.6
2e, 2r, 3 100 10.0 -17.1 10.0 -18.6 10.0 -21.8 10.0 -25.3 10.0 -29.0 11.2 -33.0 12.7 -37.3 14.2 -41.8
Hip Roof > 27 to 45 degrees 1 10 10.2 -20.3 11.1 -22.1 13.0 -26.0 15.1 -30.1 17.3 -34.6 19.7 -39.3 22.2 -44.4 24.9 -49.8
1 20 10.0 -18.0 10.0 -19.6 11.3 -23.0 13.1 -26.7 15.1 -30.7 17.1 -34.9 19.4 -39.4 21.7 -44.2
1 50 10.0 -15.0 10.0 -16.3 10.0 -19.2 10.5 -22.2 12.1 -25.5 13.8 -29.0 15.5 -32.8 17.4 -36.7
1 100 10.0 -12.7 10.0 -13.8 10.0 -16.2 10.0 -18.8 10.0 -21.6 11.2 -24.6 12.7 -27.8 14.2 -31.1
2e 10 10.2 -24.2 11.1 -26.3 13.0 -30.9 15.1 -35.9 17.3 -41.2 19.7 -46.8 22.2 -52.9 24.9 -59.3
2e 20 10.0 -19.1 10.0 -20.8 11.3 -24.4 13.1 -28.3 15.1 -32.5 17.1 -37.0 19.4 -41.8 21.7 -46.8
2e 50 10.0 -11.9 10.0 -12.9 10.0 -15.1 10.5 -17.6 12.1 -20.2 13.8 -22.9 15.5 -25.9 17.4 -29.0
2e 100 10.0 -11.9 10.0 -12.9 10.0 -15.1 10.0 -17.6 10.0 -20.2 11.2 -22.9 12.7 -25.9 14.2 -29.0
2r 10 10.2 -30.6 11.1 -33.3 13.0 -39.1 15.1 -45.4 17.3 -52.1 19.7 -59.2 22.2 -66.9 24.9 -75.0
2r 20 10.0 -25.7 10.0 -28.0 11.3 -32.8 13.1 -38.1 15.1 -43.7 17.1 -49.8 19.4 -56.2 21.7 -63.0
2r 50 10.0 -19.2 10.0 -20.9 10.0 -24.5 10.5 -28.4 12.1 -32.6 13.8 -37.1 15.5 -41.9 17.4 -47.0
2r 100 10.0 -14.3 10.0 -15.5 10.0 -18.2 10.0 -21.2 10.0 -24.3 11.2 -27.6 12.7 -31.2 14.2 -35.0
3 10 10.2 -32.7 11.1 -35.6 13.0 -41.7 15.1 -48.4 17.3 -55.6 19.7 -63.2 22.2 -71.4 24.9 -80.0
3 20 10.0 -24.6 10.0 -26.7 11.3 -31.4 13.1 -36.4 15.1 -41.8 17.1 -47.5 19.4 -53.7 21.7 -60.2
3 50 10.0 -14.3 10.0 -15.5 10.0 -18.2 10.5 -21.2 12.1 -24.3 13.8 -27.6 15.5 -31.2 17.4 -35.0
3 100 10.0 -14.3 10.0 -15.5 10.0 -18.2 10.0 -21.2 10.0 -24.3 11.2 -27.6 12.7 -31.2 14.2 -35.0
Walls 4 10 14.3 -15.5 15.5 -16.9 18.2 -19.8 21.2 -22.9 24.3 -26.3 27.6 -30.0 31.2 -33.8 35.0 -37.9
4 20 13.6 -14.8 14.8 -16.1 17.4 -19.0 20.2 -22.0 23.2 -25.2 26.4 -28.7 29.8 -32.4 33.4 -36.3
4 50 12.8 -14.0 13.9 -15.2 16.3 -17.9 19.0 -20.7 21.8 -23.8 24.8 -27.1 27.9 -30.6 31.3 -34.3
4 100 12.1 -13.3 13.2 -14.5 15.5 -17.1 18.0 -19.8 20.6 -22.7 23.5 -25.8 26.5 -29.2 29.7 32.7
4 500 10.6 -11.9 11.6 -12.9 13.6 -15.1 15.8 -17.6 18.1 -20.2 20.6 -22.9 23.3 -25.9 26.1 -29.0
5 10 14.3 -19.1 15.5 -20.8 18.2 -24.4 21.2 -28.3 24.3 -32.5 27.6 -37.0 31.2 -41.8 35.0 -46.8
5 20 13.6 -17.8 14.8 -19.4 17.4 -22.8 20.2 -26.4 23.2 -30.3 26.4 -34.5 29.8 -38.9 33.4 -43.6
5 50 12.8 -16.1 13.9 -17.6 16.3 -20.6 19.0 -23.9 21.8 -27.5 24.8 -31.2 27.9 -35.3 31.3 -39.5
5 100 12.1 -14.8 13.2 -16.1 15.5 -19.0 18.0 -22.0 20.6 -25.2 23.5 -28.7 26.5 -32.4 29.7 -36.3
5 500 10.6 -11.9 11.6 -12.9 13.6 -15.1 15.8 -17.6 18.1 -20.2 20.6 -22.9 23.3 -25.9 26.1 -29.0
For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2, 1 mile per hour = 0.447 m/s, 1 pound per square foot = 0.0479 kPa.
  1. The effective wind area shall be equal to the span length multiplied by an effective width. This width shall be permitted to be not less than one-third the span length. For cladding fasteners, the effective wind area shall not be greater than the area that is tributary to an individual fastener.
  2. For effective areas between those given, the load shall be interpolated or the load associated with the lower effective area shall be used.
  3. Table values shall be adjusted for height and exposure by multiplying by the adjustment coefficient in Table R301.2(3).
  4. See Figure R301.2(7) for location of zones.
  5. Plus and minus signs signify pressures acting toward and away from the building surfaces.
  6. Table values have been multiplied by 0.6 to convert component and cladding pressures to ASD.
  7. Loads in Zone 1' are permitted to be determined in accordance with ASCE 7.
  8. Where the ratio of the building mean roof height to length or width is less than 0.8, uplift loads are permitted to be determined in accordance with ASCE 7.
TABLE R301.2(3)
HEIGHT AND EXPOSURE ADJUSTMENT COEFFICIENTS FOR TABLE R301.2(2)
MEAN ROOF HEIGHT
(ft)
 EXPOSURE CATEGORY
B C D
15 0.82 1.21 1.47
20 0.89 1.29 1.55
25 0.94 1.35 1.61
30 1.00 1.40 1.66
35 1.05 1.45 1.70
40 1.09 1.49 1.74
45 1.12 1.53 1.78
50 1.16 1.56 1.81
55 1.19 1.59 1.84
60 1.22 1.62 1.87
TABLE R301.2(4)
NOMINAL (ASD) GARAGE DOOR WIND LOADS FOR A BUILDING WITH A MEAN ROOF HEIGHT OF 30 FEET LOCATED IN EXPOSURE B (PSF) 1, 2, 3, 4, 5
Door Size ULTIMATE DESIGN WIND SPEED (Vult) DETERMINED IN ACCORDANCE WITH SECTION R301.2.1 (MPH—3 SECOND GUST)
Width
(ft)
 Height
(ft)
 100 mph 110 mph 120 mph 130 mph 140 mph 150 mph 160 mph 170 mph 180 mph 190 mph 200 mph
9 7 +10.0 -10.9 +11.4 -12.9 +13.7 -15.5 +16.1 -18.2 +18.5 -20.9 +21.3 -24.1 +24.3 -27.5 +27.6 -31.2 +30.6 -34.6 +34.2 -38.6 +38.0 -43.0
16 7 +10.0 -10.3 +10.9 -12.2 +13.1 -14.6 +15.5 -17.2 +17.7 -19.7 +20.4 -22.7 +23.3 -26.0 +26.4 -29.4 +29.3 -32.6 +32.7 -36.5 +36.4 -40.6
78 mph 85 mph 93 mph 101 mph 108 mph 116 mph 124 mph 132 mph 139 mph 147 mph 155 mph
Nominal Design Wind Speed (Vasd) converted from Vult per Section R301.2.1.3
For SI: 1 foot = 304.8 mm, 1 mile per hour = 1.609 km/h, 1 psf = 47.88 N/m2.
  1. For door sizes or wind speeds between those given above the load may be interpolated, otherwise use the load associated with the lower door size.
  2. Table values shall be adjusted for height and exposure by multiplying by the adjustment coefficient in Table R301.2(3). Minimum positive wind load shall be 10 psf and minimum negative wind load shall be 10 psf.
  3. Plus and minus signs signify pressures acting toward and away from the building surfaces.
  4. Negative pressures assume door has 2 feet of width in building's end zone.
  5. Table values include the 0.6 load reduction factor.
For SI: °C = [(°F)-32]/1.8.
FIGURE R301.2(1)
ISOLINES OF THE 971/2 -PERCENT WINTER (DECEMBER, JANUARY AND FEBRUARY) DESIGN TEMPERATURES (°F)
FIGURE R301.2(2)
SEISMIC DESIGN CATEGORIES—SITE CLASS D
  1. Alaska and Hawaii are classified as severe and negligible, respectively.
  2. Lines defining areas are approximate only. Local conditions may be more or less severe than indicated by region classification. A severe classification is where weather conditions result in significant snowfall combined with extended periods during which there is little or no natural thawing causing deicing salts to be used extensively.
FIGURE R301.2(3)
WEATHERING PROBABILITY MAP FOR CONCRETEa, b
FIGURE R301.2(4)
ULTIMATE DESIGN WIND SPEEDS Vult
Figure R301.2(4)A
Ultimate Design Wind Speed.
Reserved.
Figure R301.2(4)B
Regions Where Wind Design Is Required.
Reserved.
For SI: 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa, 1 mile = 1.61 km.
  1. In CS areas, site-specific Case Studies are required to establish ground snow loads. Extreme local variations in ground snow loads in theses areas preclude mapping at this scale.
  2. Numbers in parentheses represent the upper elevation limits in feet for the ground snow load values presented below. Site-specific case studies are required to establish ground snow loads at elevations not covered.
FIGURE R301.2(5)
GROUND SNOW LOADS, Pg, FOR THE UNITED STATES (lb/ft2)
Note: Lines defining areas are approximate only. Local conditions may be more or less severe than indicated by the region classification.
FIGURE R301.2(6)
TERMITE INFESTATION PROBABILITY MAP
For SI: 1 foot = 304.8 mm, 1 degree = 0.0175 rad.
Note: a = 4 feet in all cases.
FIGURE R301.2(7)
COMPONENT AND CLADDING PRESSURE ZONES
Upcodes Diagrams

R301.2.1 Wind Design Criteria

Buildings and portions thereof shall be constructed in accordance with the wind provisions of this code using the ultimate design wind speed in Table R301.2(1) as determined from Figure R301.2(4). Where different construction methods and structural materials are used for various portions of a building, the applicable requirements of this section for each portion shall apply. Where not otherwise specified, the wind loads listed in Table R301.2(2) adjusted for height and exposure using Table R301.2(3) shall be used to determine design load performance requirements for wall coverings, curtain walls, roof coverings, exterior windows, skylights, and exterior doors (other than garage doors). Where loads for garage doors are not otherwise specified, the loads listed in Table R301.2(4) adjusted for height and exposure using Table R301.2(3) shall be used to determine design load performance requirements. Asphalt shingles shall be designed for wind speeds in accordance with Section R905.2.4. Metal roof shingles shall be designed for wind speeds in accordance with Section R905.4.4. A continuous load path shall be provided to transmit the applicable uplift forces from the roof assembly to the foundation.

R301.2.1.1 Wind Design Required

In regions where the ultimate design wind speed, Vult, from Figure R301.2(4) equals or exceeds 115 miles per hour (51 m/s), the design of concrete, masonry, wood and steel buildings for wind loads shall be in accordance with one or more of the following methods:
  1. AWC Wood Frame Construction Manual (WFCM).
  2. Concrete and masonry walls are permitted to be designed in accordance with ICC Standard for Residential Construction in High-Wind Regions (ICC 600).
  3. ASCE Minimum Design Loads for Buildings and Other Structures (ASCE 7).
  4. AISI Standard for Cold-Formed Steel Framing—Prescriptive Method For One- and Two-Family Dwellings (AISI S230).
  5. Florida Building Code, Building; or
  6. The MAF Guide to Concrete Masonry Residential Construction in High Wind Areas shall be permitted for applicable concrete masonry buildings for a basic wind speed of 130 mph (58 m/s) or less in Exposure B and 110 mph (49 m/s) or less in Exposure C in accordance with Figure R301.2(4) as converted in accordance with R301.2.1.3.
    Exceptions:
    1. Footings and foundations shall comply with Chapter 4.
    2. Exterior windows and doors shall comply with Section R609.
    3. For structural insulated panels, the provisions of this code apply in accordance with the limitations of Section R610.
    4. Exterior wall coverings and soffits shall comply with Chapter 7.
    5. Roof sheathing shall be attached in accordance with Section R803.
    6. Roof coverings shall comply with Chapter 9.
    7. For concrete construction, the provisions of this code apply in accordance with the limitations of Section R608.2.
The elements of design not addressed by the methods in Items 1 through 6 shall be in accordance with the provisions of this code.

R301.2.1.1.1 Sunrooms

Sunrooms shall comply with AAMA/NSA 2100. For the purpose of applying the criteria of AAMA/NSA 2100 based on the intended use, sunrooms shall be identified as one of the following categories by the permit applicant, design professional or the property owner or owner's agent in the construction documents. Component and cladding pressures shall be used for the design of elements that do not qualify as main windforce-resisting systems. Main windforce-resisting system pressures shall be used for the design of elements assigned to provide support and stability for the overall sunroom.
  • A thermally isolated sunroom with walls that are open or enclosed with insect screening or 0.5 mm (20 mil) maximum thickness plastic film. The space is nonhabitable and unconditioned.
  • A thermally isolated sunroom with enclosed walls. The openings are enclosed with translucent or transparent plastic or glass. The space is nonhabitable and unconditioned.
  • A thermally isolated sunroom with enclosed walls. The openings are enclosed with translucent or transparent plastic or glass. The sunroom fenestration complies with additional requirements for air infiltration resistance and water penetration resistance. The space is nonhabitable and unconditioned.
  • A thermally isolated sunroom with enclosed walls. The sunroom is designed to be heated or cooled by a separate temperature control or system and is thermally isolated from the primary structure. The sunroom fenestration complies with additional requirements for water penetration resistance, air infiltration resistance and thermal performance. The space is nonhabitable and conditioned.
  • A sunroom with enclosed walls. The sunroom is designed to be heated or cooled and is open to the main structure. The sunroom fenestration complies with additional requirements for water penetration resistance, air infiltration resistance and thermal performance. The space is habitable and conditioned.

R301.2.1.1.1.1 Aluminum Structure Design

The AAF Guide to Aluminum Construction in High-Wind Areas shall be permitted for the construction of the aluminum structures therein addressed. Screen enclosures shall be permitted to be designed in accordance with the Florida Building Code, Building Section 2002. Wind speeds shall be as for Risk Category I of Figure 1609.3(4) of the Florida Building Code, Building. Vinyl, tempered glass, and acrylic panels shall be permitted and shall be removable. Removable panels shall be identified as removable by a decal. The identification decal shall essentially state: "Removable panel SHALL be removed when wind speeds exceed 75 mph (34 m/s)." Decals shall be placed such that the decal is visible when the panel is installed.

R301.2.1.1.2 Alternative Design Method for Screen Enclosure

  1. The purpose of this section is to provide an alternate method for designing aluminum screen enclosures as defined by the Florida Building Code, permitting the loads of the structural frame to be based on portions of the screen in the screen walls removed, retracted, moved to the open position, or cut. The use of framing materials other than aluminum is allowed in accordance with Section 104.11 of the Florida Building Code, Building. The method applies only to walls and roofs with 100-percent screen.
    1. Screen enclosure frames designed in accordance with the screen removal alternates of this section, shall be designed using signed and sealed site-specific engineering and shall be designed in accordance with the wind load provisions of the Florida Building Code, Building, Section 1609.1.1,
    2. Designs that consider these screen alternates shall comply with Florida Building Code, Building Section 2002.4 and Table 2002.4, using the 110 mph column as modified by Table 2002.4A with all screen panels in place.
    3. Designs using strength design or load and resistance factor design in accordance with the Florida Building Code, Building, Section 1605.2 or allowable stress design methods of the Florida Building Code, Building, Section 1605.3.1 shall be permitted.
    4. The design shall be by rational analysis or by 3D Finite Element Analysis. Either method will be acceptable.
  2. Where screen enclosures are designed in accordance with the screen removal alternates of this section, removable screen may consist of removable panels, retractable panels, or by designating specific screen panels in the design in which the screen is to be removed by cutting the screen. Removable panels shall be removed; retractable panels shall be placed in the retracted position without increasing the load on the affected area. Screen designated in the design to be cut shall be completely cut when wind speeds are forecast to exceed 75 mph.
  3. Where screen enclosures designed in accordance with the screen removal alternates of this section serve as the barrier required by Section R4501.17.1, the required minimum height of the barrier shall be maintained when screen panels are retracted, removed, moved to the open position, or cut.
  4. Where screen enclosures are designed in accordance with the screen removal alternates of this section, retractable screen panels, removable screen panels, and screen panels identified to be cut shall be clearly identified on adjacent structural members with highly visible permanent labels, at each panel, or by other means approved by the local building department.
  5. Where screen enclosures are designed in accordance with the screen removal alternates of this section, the retraction of screen panels, removal of screen panels, or cutting of screen panels shall not require the use of ladders or scaffolding.
  6. Engineering documents submitted with building permit applications shall identify the panels to be removed, retracted, opened, or cut.
  7. Where screen enclosures are designed in accordance with the screen removal alternates of this section based on removing screen panels by cutting the screen, the contractor shall provide replacement screen for a one-time replacement of all screen and spline designated by the design to be cut.
  8. Where screen enclosures are designed in accordance with the screen removal alternates of this section, the contractor shall provide written notice to the owner and the local building code enforcement department that the owner must retract, remove, or cut a panel or panels of the screen enclosure in accordance with the project engineering design or the manufacturer's instructions when wind speeds are expected to exceed 75 mph.

R301.2.1.2 Protection of Openings

Exterior glazed openings in buildings located in windborne debris regions shall be protected from windborne debris. Glazed opening protection for windborne debris shall meet the requirements of the Large Missile Test of ASTM E1996 and ASTM E1886 as modified in Section 301.2.1.2.1, TAS 201, 202 and 203, or AAMA 506, as applicable. Garage door glazed opening protection for windborne debris shall meet the requirements of an approved impact-resisting standard or ANSI/DASMA 115.
  1. Openings in sunrooms, balconies or enclosed porches constructed under existing roofs or decks are not required to be protected provided the spaces are separated from the building interior by a wall and all openings in the separating wall are protected in accordance with this section. Such space shall be permitted to be designed as either partially enclosed or enclosed structures.
  2. Storage sheds that are not designed for human habitation and that have a floor area of 720 square feet (67 m2) or less are not required to comply with the mandatory wind-borne debris impact standard of this code.
Exception: Wood structural panels with a thickness of not less than 7/16 inch (11 mm) and a span between lines of fasteners of 44 inches (1118 mm) shall be permitted for opening protection in buildings with a mean roof height of 33 feet or less in locations where Vult is 180 mph or less. Panels shall be precut to overlap the wall such that they extend a minimum of 2 inches (50.8 mm) beyond the lines of fasteners and attached to the framing surrounding the opening containing the product with the glazed opening. Panels shall be predrilled as required for the attachment method and secured with corrosion-resistant attachment hardware permanently installed on the building.
  1. Attachments shall be designed to resist the component and cladding loads determined in accordance with either Table R301.2(2) or ASCE 7, with the permanent corrosion-resistant attachment hardware provided and anchors permanently installed on the building.
  2. As an alternative, panels shall be fastened at 16 inches (406.4 mm) o.c. along the edges of the opposing long sides of the panel.
    1. For wood frame construction, fasteners shall be located on the wall such that they are embedded into the wall framing members, nominally a minimum of 1 inch (25.4 mm) from the edge of the opening and 2 inches (50.8 mm) inward from the panel edge. Permanently installed anchors used for buildings with wood frame wall construction shall have the threaded portion that will be embedded into the wall framing based on 1/4-inch (6.35 mm) lag-screws and shall be long enough to penetrate through the exterior wall covering with sufficient embedment length to provide an allowable minimum 300 pounds ASD design withdrawal capacity.
    2. For concrete or masonry wall construction, fasteners shall be located on the wall a minimum of 1.5 inches (37.9 mm) from the edge of the opening and 2 inches (50.8 mm) inward of the panel edge. Permanently installed anchors in Concrete or masonry wall construction shall have an allowable minimum 300 pounds ASD design withdrawal capacity and an allowable minimum 525 pounds ASD design shear capacity with a 1.5 inch edge distance. Hex nuts, washered wing-nuts, or bolts used to attach the wood structural panels to the anchors shall be minimum 1/4-inch hardware and shall be installed with or have integral washers with a minimum 1-inch outside diameter.
    3. Vibration-resistant alternative attachments designed to resist the component and cladding loads determined in accordance with provisions of Table R301.2(2) or ASCE 7 shall be permitted.
Table R301.2.1.2
Windborne Debris Protection Fastening Schedule for Wood Structural Panels.
Reserved.

R301.2.1.2.1 Application of ASTM E1996

The text of Section 2.2 of ASTM E1996 shall be substituted as follows:
2.2 ASCE Standard:
ASCE 7-10 American Society of Civil Engineers Minimum Design Loads for Buildings and Other Structures
The text of Section 6.2.2 of ASTM E1996 shall be substituted as follows:
6.2.2 Unless otherwise specified, select the wind zone based on the ultimate design wind speed, Vult, as follows:
6.2.2.1 Wind Zone 1—130 mph ≤ ultimate design wind speed, Vult < 140 mph.
6.2.2.2 Wind Zone 2—140 mph ≤ ultimate design wind speed, Vult < 150 mph at greater than 1 mile (1.6 km) from the coastline. The coastline shall be measured from the mean high water mark.
6.2.2.3 Wind Zone 3—150 mph (58 m/s) ≤ ultimate design wind speed, Vult ≤ 170 mph (76 m/s), or 140 mph (54 m/s) ≤ ultimate design wind speed, Vult ≤ 170 mph (76 m/s) and within 1 mile (1.6 km) of the coastline. The coastline shall be measured from the mean high water mark.
6.2.2.4 Wind Zone 4—ultimate design wind speed, Vult > 170 mph (76 m/s).

R301.2.1.3 Wind Speed Conversion

Where referenced documents are based on nominal design wind speeds and do not provide the means for conversion between ultimate design wind speeds and nominal design wind speeds, the ultimate design wind speeds, Vult, of Figure R301.2(4) shall be converted to nominal design wind speeds, Vasd, using Table R301.2.1.3.
TABLE R301.2.1.3
WIND SPEED CONVERSIONSa
Vult 110 115 120 130 140 150 160 170 180 190 200
Vasd 85 89 93 101 108 116 124 132 139 147 155
For SI: 1 mile per hour = 0.447 m/s.
  1. Linear interpolation is permitted.

R301.2.1.4 Exposure Category

For each wind direction considered, an exposure category that adequately reflects the characteristics of ground surface irregularities shall be determined for the site at which the building or structure is to be constructed. For a site located in the transition zone between categories, the category resulting in the largest wind forces shall apply. Account shall be taken of variations in ground surface roughness that arise from natural topography and vegetation as well as from constructed features. For a site where multiple detached one- and two-family dwellings, townhouses or other structures are to be constructed as part of a subdivision or master-planned community, or are otherwise designated as a developed area by the authority having jurisdiction, the exposure category for an individual structure shall be based upon the site conditions that will exist at the time when all adjacent structures on the site have been constructed, provided that their construction is expected to begin within one year of the start of construction for the structure for which the exposure category is determined.
Exception: An intermediate exposure between the exposure categories defined is permitted in a transition zone provided that it is determined by a rational analysis method.

R301.2.1.4.1 Wind Directions and Sectors

For each selected wind direction at which the wind loads are to be evaluated, the exposure of the building or structure shall be determined for the two upwind sectors extending 45 degrees (0.79 rad) either side of the selected wind direction. The exposures in these two sectors shall be determined in accordance with Sections R301.2.1.4.2 and R301.2.1.4.3 and the exposure resulting in the highest wind loads shall be used to represent winds from that direction.

R301.2.1.4.2 Surface Roughness Categories

A ground surface roughness within each 45-degree (0.79 rad) sector shall be determined for a distance upwind of the site as defined in Section R301.2.1.4.3 from the categories defined below, for the purpose of assigning an exposure category as defined in Section R301.2.1.4.3.
  • Urban and suburban areas, wooded areas or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger.
  • Open terrain with scattered obstructions having heights generally less than 30 feet (9144 mm). This category includes flat open country and grasslands. This Surface Roughness shall also apply to any building located within Surface Roughness B-type terrain where the building is within 100 feet (30.5 m) horizontally in any direction of open areas of Surface Roughness C- or D-type terrain that extends more than 600 feet (182.9 m) and width greater than 150 feet (45.7 m) in the upwind direction.
  • Flat, unobstructed areas and water surfaces. This category includes smooth mud flats, salt flats and unbroken ice.

R301.2.1.4.3 Exposure Categories

An exposure category shall be determined in accordance with the following:
  • For buildings with a mean roof height of less than or equal to 30 feet (9144 mm), Exposure B shall apply where the ground surface roughness, as defined by Surface Roughness B, prevails in the upwind direction for a distance of at least 1,500 feet (457 m). For buildings with a mean roof height greater than 30 feet (9144 mm), Exposure B shall apply where Surface Roughness B prevails in the upwind direction for a distance of at least 2,600 feet (792 m) or 20 times the height of the building, whichever is greater.
  • Exposure C shall apply for all cases where Exposures B or D do not apply.
  • Exposure D shall apply where the ground surface roughness, as defined by Surface Roughness D, prevails in the upwind direction for a distance of at least 5,000 feet (1524 m) or 20 times the height of the building, whichever is greater. Exposure D shall also apply where the ground surface roughness immediately upwind of the site is B or C, and the site is within a distance of 600 feet (183 m) or 20 times the building height, whichever is greater, from an Exposure D condition as defined in the previous sentence.

R301.2.1.5 Topographic Wind Effects

In areas designated in Table R301.2(1) as having local historical data documenting structural damage to buildings caused by wind speed-up at isolated hills, ridges and escarpments that are abrupt changes from the general topography of the area, topographic wind effects shall be considered in the design of the building in accordance with Section R301.2.1.5.1 or in accordance with the provisions of ASCE 7. See Figure R301.2.1.5.1(1) for topographic features for wind speed-up effect.
In these designated areas, topographic wind effects shall apply only to buildings sited on the top half of an isolated hill, ridge or escarpment where all of the following conditions exist:
  1. The average slope of the top half of the hill, ridge or escarpment is 10 percent or greater.
  2. The hill, ridge or escarpment is 60 feet (18 288 mm) or greater in height for Exposure B, 30 feet (9144 mm) or greater in height for Exposure C, and 15 feet (4572 mm) or greater in height for Exposure D.
  3. The hill, ridge or escarpment is isolated or unobstructed by other topographic features of similar height in the upwind direction for a distance measured from its high point of 100 times its height or 2 miles (3.2 km), whichever is less. See Figure R301.2.1.5.1(3) for upwind obstruction.
  4. The hill, ridge or escarpment protrudes by a factor of two or more above the height of other upwind topographic features located in any quadrant within a radius of 2 miles (3.2 km) measured from its high point.

R301.2.1.5.1 Simplified Topographic Wind Speed-Up Method

As an alternative to the ASCE 7 topographic wind provisions, the provisions of Section R301.2.1.5.1 shall be permitted to be used to design for wind speed-up effects, where required by Section R301.2.1.5.
Structures located on the top half of isolated hills, ridges or escarpments meeting the conditions of Section R301.2.1.5 shall be designed for an increased basic wind speed as determined by Table R301.2.1.5.1. On the high side of an escarpment, the increased basic wind speed shall extend horizontally downwind from the edge of the escarpment 1.5 times the horizontal length of the upwind slope (1.5L) or 6 times the height of the escarpment (6H), whichever is greater. See Figure R301.2.1.5.1(2) for where wind speed increase is applied.
TABLE R301.2.1.5.1
ULTIMATE DESIGN WIND SPEED MODIFICATION FOR TOPOGRAPHIC WIND EFFECTa, b
ULTIMATE DESIGN
WIND SPEED FROM
FIGURE R301.2(4)
(mph)
 AVERAGE SLOPE OF THE TOP HALF OF HILL, RIDGE OR ESCARPMENT (percent)
0.10 0.125 0.15 0.175 0.20 0.23 0.25
Required ultimate design wind speed-up, modified for topographic wind speed-up (mph)
110 132 137 142 147 152 158 162
115 138 143 148 154 159 165 169
120 144 149 155 160 166 172 176
130 156 162 168 174 179 N/A N/A
140 168 174 181 N/A N/A N/A N/A
150 180 N/A N/A N/A N/A N/A N/A
For SI: 1 mile per hour = 0.447 m/s, 1 foot = 304.8 mm.
  1. Table applies to a feature height of 500 feet or less and dwellings sited a distance equal or greater than half the feature height.
  2. Reserved.
Note: H/2 determines the measurement point for Lh. L is twice Lh.
FIGURE R301.2.1.5.1(1)
TOPOGRAPHIC FEATURES FOR WIND SPEED-UP EFFECT
FIGURE R301.2.1.5.1(2)
ILLUSTRATION OF WHERE ON A TOPOGRAPHIC FEATURE, WIND SPEED INCREASE IS APPLIED
FIGURE R301.2.1.5.1(3)
UPWIND OBSTRUCTION

R301.2.1.6 Testing to Allowable or Nominal Loads

Where testing for wind load resistance is based on allowable or nominal wind loads, the design wind loads determined in accordance with ASCE 7 or Section 1609 of the Florida Building Code, Building are permitted to be multiplied by 0.6 for the purposes of the wind load resistance testing.

R301.2.2 Seismic Provisions

The seismic provisions of this code shall apply as follows:
  1. Townhouses in Seismic Design Categories C, D0, D1 and D2.
  2. Detached one- and two-family dwellings in Seismic Design Categories, D0, D1 and D2.
Upcodes Diagrams

R301.2.2.1 Determination of Seismic Design Category

Buildings shall be assigned a seismic design category in accordance with Figure R301.2(2).

R301.2.2.1.1 Alternative Determination of Seismic Design Category

The seismic design categories and corresponding short-period design spectral response accelerations, SDS shown in Figure R301.2(2) are based on soil Site Class D, as defined in Section 1613.3.2 of the Florida Building Code, Building. If soil conditions are other than Site Class D, the shortperiod design spectral response accelerations, SDS, for a site can be determined in accordance with Section 1613.3 of the Florida Building Code, Building. The value of SDS determined in accordance with Section 1613.3 of the Florida Building Code, Building is permitted to be used to set the seismic design category in accordance with Table R301.2.2.1.1, and to interpolate other seismic design requirements of this code.
TABLE R301.2.2.1.1
SEISMIC DESIGN CATEGORY DETERMINATION
CALCULATED SDS SEISMIC DESIGN CATEGORY
SDS ≤ 0.17g A
0.17g < SDS ≤ 0.33g B
0.33g < SDS ≤ 0.50g C
0.50g < SDS ≤ 0.67g D0
0.67g < SDS ≤ 0.83g D1
0.83g < SDS ≤ 1.25g D2
1.25g < SDS E

R301.2.2.1.2 Alternative Determination of Seismic Design Category E

Buildings located in Seismic Design Category E in accordance with Figure R301.2(2) are permitted to be reclassified as being in Seismic Design Category D2 provided that one of the following is done:
  1. A more detailed evaluation of the seismic design category is made in accordance with the provisions and maps of the Florida Building Code, Building. Buildings located in Seismic Design Category E in accordance with Table R301.2.2.1.1, but located in Seismic Design Category D in accordance with the Florida Building Code, Building, shall be permitted to be designed using the Seismic Design Category D2 requirements of this code.
  2. Buildings located in Seismic Design Category E that conform to the following additional restrictions are permitted to be constructed in accordance with the provisions for Seismic Design Category D2 of this code:
    1. 2.1. All exterior shear wall lines or braced wall panels are in one plane vertically from the foundation to the uppermost story.
    2. 2.2. Floors shall not cantilever past the exterior walls.
    3. 2.3. The building is within the requirements of Section R301.2.2.2.5 for being considered as regular.

R301.2.2.2 Seismic Design Category C

Structures assigned to Seismic Design Category C shall conform to the requirements of this section.

R301.2.2.2.1 Weights of Materials

Average dead loads shall not exceed 15 pounds per square foot (720 Pa) for the combined roof and ceiling assemblies (on a horizontal projection) or 10 pounds per square foot (480 Pa) for floor assemblies, except as further limited by Section R301.2.2. Dead loads for walls above grade shall not exceed:
  1. Fifteen pounds per square foot (720 Pa) for exterior light-frame wood walls.
  2. Fourteen pounds per square foot (670 Pa) for exterior light-frame cold-formed steel walls.
  3. Ten pounds per square foot (480 Pa) for interior light-frame wood walls.
  4. Five pounds per square foot (240 Pa) for interior light-frame cold-formed steel walls.
  5. Eighty pounds per square foot (3830 Pa) for 8-inch-thick (203 mm) masonry walls.
  6. Eighty-five pounds per square foot (4070 Pa) for 6-inch-thick (152 mm) concrete walls.
  7. Ten pounds per square foot (480 Pa) for SIP walls.
Exceptions:
  1. Roof and ceiling dead loads not exceeding 25 pounds per square foot (1190 Pa) shall be permitted provided that the wall bracing amounts are increased as specified in the AWC WFCM.
  2. Light-frame walls with stone or masonry veneer shall be permitted in accordance with the provisions of Sections R702.1 and R703.
  3. Fireplaces and chimneys shall be permitted in accordance with Chapter 10.
Upcodes Diagrams

R301.2.2.2.2 Stone and Masonry Veneer

Anchored stone and masonry veneer shall comply with the requirements of Sections R702.1 and R703.

R301.2.2.2.3 Masonry Construction

Masonry construction shall comply with the requirements of Section R606.1.

R301.2.2.2.4 Concrete Construction

Detached one- and two-family dwellings with exterior above-grade concrete walls shall comply with the requirements of Section R608, PCA 100 or shall be designed in accordance with ACI 318. Townhouses with above-grade exterior concrete walls shall comply with the requirements of PCA 100 or shall be designed in accordance with ACI 318.

R301.2.2.2.5 Irregular Buildings

The seismic provisions of this code shall not be used for irregular structures located in Seismic Design Categories C, D0, D1 and D2. Irregular portions of structures shall be designed in accordance with accepted engineering practice to the extent the irregular features affect the performance of the remaining structural system. Where the forces associated with the irregularity are resisted by a structural system designed in accordance with accepted engineering practice, design of the remainder of the building shall be permitted using the provisions of this code. A building or portion of a building shall be considered to be irregular where one or more of the following conditions occur:
  1. Where exterior shear wall lines or braced wall panels are not in one plane vertically from the foundation to the uppermost story in which they are required.
    Exception: For wood light-frame construction, floors with cantilevers or setbacks not exceeding four times the nominal depth of the wood floor joists are permitted to support braced wall panels that are out of plane with braced wall panels below provided that:
    1. Floor joists are nominal 2 inches by 10 inches (51 mm by 254 mm) or larger and spaced not more than 16 inches (406 mm) on center.
    2. The ratio of the back span to the cantilever is not less than 2 to 1.
    3. Floor joists at ends of braced wall panels are doubled.
    4. For wood-frame construction, a continuous rim joist is connected to ends of cantilever joists. When spliced, the rim joists shall be spliced using a galvanized metal tie not less than 0.058 inch (1.5 mm) (16 gage) and 11/2 inches (38 mm) wide fastened with six 16d nails on each side of the splice or a block of the same size as the rim joist of sufficient length to fit securely between the joist space at which the splice occurs fastened with eight 16d nails on each side of the splice; and
    5. Gravity loads carried at the end of cantilevered joists are limited to uniform wall and roof loads and the reactions from headers having a span of 8 feet (2438 mm) or less.
  2. Where a section of floor or roof is not laterally supported by shear walls or braced wall lines on all edges.
    Exception: Portions of floors that do not support shear walls or braced wall panels above, or roofs, shall be permitted to extend not more than 6 feet (1829 mm) beyond a shear wall or braced wall line.
  3. Where the end of a braced wall panel occurs over an opening in the wall below and ends at a horizontal distance greater than 1 foot (305 mm) from the edge of the opening. This provision is applicable to shear walls and braced wall panels offset in plane and to braced wall panels offset out of plane as permitted by the exception to Item 1.
    Exception: For wood light-frame wall construction, one end of a braced wall panel shall be permitted to extend more than 1 foot (305 mm) over an opening not more than 8 feet (2438 mm) in width in the wall below provided that the opening includes a header in accordance with the following:
    1. The building width, loading condition and framing member species limitations as specified in the AWC WFCM shall apply; and
    2. Not less than one 2 × 12 or two 2 × 10 for an opening not more than 4 feet (1219 mm) wide; or
    3. Not less than two 2 × 12 or three 2 × 10 for an opening not more than 6 feet (1829 mm) in width; or
    4. Not less than three 2 × 12 or four 2 × 10 for an opening not more than 8 feet (2438 mm) in width; and
    5. The entire length of the braced wall panel does not occur over an opening in the wall below.
  4. Where an opening in a floor or roof exceeds the lesser of 12 feet (3658 mm) or 50 percent of the least floor or roof dimension.
  5. Where portions of a floor level are vertically offset.
    Exceptions:
    1. Framing supported directly by continuous foundations at the perimeter of the building.
    2. For wood light-frame construction, floors shall be permitted to be vertically offset when the floor framing is lapped or tied together as required by Section R502.2.
  6. Where shear walls and braced wall lines do not occur in two perpendicular directions.
  7. Where stories above grade plane partially or completely braced by wood wall framing in accordance with Section R602 or cold-formed steel wall framing in accordance with Section R603 include masonry or concrete construction. Where this irregularity applies, the entire story shall be designed in accordance with accepted engineering practice.
    Exception: Fireplaces, chimneys and masonry veneer as permitted by this code.
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R301.2.2.3 Seismic Design Categories D0, D1 and D2

Structures assigned to Seismic Design Categories D0, D1 and D2 shall conform to the requirements for Seismic Design Category C and the additional requirements of this section.

R301.2.2.3.1 Height Limitations

Wood-framed buildings shall be limited to three stories above grade plane or the limits given in the AWC WFCM. Cold-formed, steel-framed buildings shall be limited to less than or equal to three stories above grade plane in accordance with AISI S230. Mezzanines as defined in Section R202 that comply with Section R325 shall not be considered as stories. Structural insulated panel buildings shall be limited to two stories above grade plane.

R301.2.2.3.2 Stone and Masonry Veneer

Anchored stone and masonry veneer shall comply with the requirements of Sections R702.1 and R703.

R301.2.2.3.3 Masonry Construction

Masonry construction in Seismic Design Categories D0, D1 and D2 shall comply with the requirements of Section R606.1.

R301.2.2.3.4 Concrete Construction

Buildings with exterior above-grade concrete walls shall comply with PCA 100 or shall be designed in accordance with ACI 318.

R301.2.2.3.5 Cold-Formed Steel Framing in Seismic Design Categories D0, D1 and D2

In Seismic Design Categories D0, D1 and D2 in addition to the requirements of this code, cold-formed steel framing shall comply with the requirements of AISI S230.

R301.2.2.3.6 Masonry Chimneys

Masonry chimneys shall be reinforced and anchored to the building in accordance with Sections R1003.3 and R1003.4.

R301.2.2.3.7 Anchorage of Water Heaters

Water heaters shall be anchored against movement and overturning in accordance with Section M1307.2.
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R301.2.2.4 Seismic Design Category E

Buildings in Seismic Design Category E shall be designed to resist seismic loads in accordance with the Florida Building Code, Building, except where the seismic design category is reclassified to a lower seismic design category in accordance with Section R301.2.2.1. Components of buildings not required to be designed to resist seismic loads shall be constructed in accordance with the provisions of this code.

R301.2.3 Snow Loads

Wood-framed construction, cold-formed, steel-framed construction and masonry and concrete construction, and structural insulated panel construction in regions with ground snow loads 70 pounds per square foot (3.35 kPa) or less, shall be in accordance with Chapters 5, 6 and 8. Buildings in regions with ground snow loads greater than 70 pounds per square foot (3.35 kPa) shall be designed in accordance with accepted engineering practice.

R301.2.4 Floodplain Construction

Buildings and structures constructed in whole or in part in flood hazard areas (including A or V Zones) as established in Table R301.2(1), and substantial improvement and repair of substantial damage of buildings and structures in flood hazard areas, shall be designed and constructed in accordance with Section R322. Buildings and structures that are located in more than one flood hazard area shall comply with the provisions associated with the most restrictive flood hazard area. Buildings and structures located in whole or in part in identified floodways shall be designed and constructed in accordance with ASCE 24.

R301.2.4.1 Alternative Provisions

As an alternative to the requirements in Section R322, ASCE 24 is permitted subject to the limitations of this code and the limitations therein.

R301.2.5 Structures Seaward of a Coastal Construction Control Line

Structures located seaward of the coastal construction control line shall be designed to resist the predicted forces of a 100-year storm event in accordance with Section 3109 of the Florida Building Code, Building.

R301.3 Story Height

The provisions of this code shall apply to buildings with story heights not exceeding the following:
  1. For wood wall framing, the story height shall be in accordance with Section R602.3.
  2. For cold-formed steel wall framing, the story height shall be in accordance with Section R603.
  3. For masonry walls, the story height shall be in accordance with Section R606.
  4. For insulating concrete form walls, the maximum story height shall not exceed 11 feet 7 inches (3531 mm) and the maximum unsupported wall height per story as permitted by Section R608 tables shall not exceed 10 feet (3048 mm).
  5. For structural insulated panel (SIP) walls, the story height shall be not greater than 11 feet 7 inches (3531 mm) and the bearing wall height per story as permitted by Section R610 tables shall not exceed 10 feet (3048 mm).
Individual walls or wall studs shall be permitted to exceed these limits as permitted by Chapter 6 provisions, provided that story heights are not exceeded. An engineered design shall be provided for the wall or wall framing members where the limits of Chapter 6 are exceeded. Where the story height limits of this section are exceeded, the design of the building, or the noncompliant portions thereof, to resist wind and seismic loads shall be in accordance with the Florida Building Code, Building.

R301.4 Dead Load

The actual weights of materials and construction shall be used for determining dead load with consideration for the dead load of fixed service equipment.
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R301.5 Live Load

The minimum uniformly distributed live load shall be as provided in Table R301.5.
TABLE R301.5
MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS (in pounds per square foot)
USE LIVE LOAD
Uninhabitable attics without storageb 10
Uninhabitable attics with limited storageb, g 20
Habitable attics and attics served with fixed stairs 30
Balconies (exterior) and deckse 40
Fire escapes 40
Guards and handrailsd 200h
Guard in-fill componentsf 50h
Passenger vehicle garagesa 50a
Rooms other than sleeping rooms 40
Sleeping rooms 30
Stairs 40c
For SI: 1 pound per square foot = 0.0479 kPa, 1 square inch = 645 mm2, 1 pound = 4.45 N.
  1. Elevated garage floors shall be capable of supporting a 2,000-pound load applied over a 20-square-inch area.
  2. Uninhabitable attics without storage are those where the clear height between joists and rafters is not more than 42 inches, or where there are not two or more adjacent trusses with web configurations capable of accommodating an assumed rectangle 42 inches in height by 24 inches in width, or greater, within the plane of the trusses. This live load need not be assumed to act concurrently with any other live load requirements.
  3. Individual stair treads shall be designed for the uniformly distributed live load or a 300-pound concentrated load acting over an area of 4 square inches, whichever produces the greater stresses.
  4. A single concentrated load applied in any direction at any point along the top.
  5. See Section R507.1 for decks attached to exterior walls.
  6. Guard in-fill components (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds on an area equal to 1 square foot. This load need not be assumed to act concurrently with any other live load requirement.
  7. Uninhabitable attics with limited storage are those where the clear height between joists and rafters is not greater than 42 inches, or where there are two or more adjacent trusses with web configurations capable of accommodating an assumed rectangle 42 inches in height by 24 inches in width, or greater, within the plane of the trusses.
    The live load need only be applied to those portions of the joists or truss bottom chords where all of the following conditions are met:
    1. The attic area is accessed from an opening not less than 20 inches in width by 30 inches in length that is located where the clear height in the attic is not less than 30 inches.
    2. The slopes of the joists or truss bottom chords are not greater than 2 inches vertical to 12 units horizontal.
    3. Required insulation depth is less than the joist or truss bottom chord member depth.
    The remaining portions of the joists or truss bottom chords shall be designed for a uniformly distributed concurrent live load of not less than 10 pounds per square foot.
  8. Glazing used in handrail assemblies and guards shall be designed with a safety factor of 4. The safety factor shall be applied to each of the concentrated loads applied to the top of the rail, and to the load on the in-fill components. These loads shall be determined independent of one another, and loads are assumed not to occur with any other live load.
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R301.6 Roof Load

The roof shall be designed for the live load indicated in Table R301.6 or the snow load indicated in Table R301.2(1), whichever is greater.
TABLE R301.6
MINIMUM ROOF LIVE LOADS IN POUNDS-FORCE PER SQUARE FOOT OF HORIZONTAL PROJECTION
ROOF SLOPE TRIBUTARY LOADED AREA IN
SQUARE FEET FOR ANY
STRUCTURAL MEMBER
0 to 200 201 to 600 Over 600
Flat or rise less than 4 inches per
foot (1:3)
 20 16 12
Rise 4 inches per foot (1:3) to
less than 12 inches per foot (1:1)
 16 14 12
Rise 12 inches per foot (1:1)
and greater
 12 12 12
For SI: 1 square foot = 0.0929 m2, 1 pound per square foot = 0.0479 kPa, 1 inch per foot = 83.3 mm/m.

R301.7 Deflection

The allowable deflection of any structural member under the live load listed in Sections R301.5 and R301.6 or wind loads determined by Section R301.2.1 shall not exceed the values in Table R301.7.
TABLE R301.7
ALLOWABLE DEFLECTION OF STRUCTURAL MEMBERSb, c
STRUCTURAL MEMBER ALLOWABLE
DEFLECTION
Rafters having slopes greater than 3:12 with
finished ceiling not attached to rafters
 L/180
Interior walls and partitions H/180
Floors L/360
Ceilings with brittle finishes (including plaster
and stucco)
 L/360
Ceilings with flexible finishes (including gypsum
board)
 L/240
All other structural members L/240
Exterior walls—wind loadsa with plaster or
stucco finish
 H/360
Exterior walls—wind loadsa with other brittle
finishes
 H/240
Exterior walls—wind loadsa with flexible finishes H/120d
Lintels supporting masonry veneer wallse L/600
Note: L = span length, H = span height.
  1. For the purpose of the determining deflection limits herein, the wind load shall be permitted to be taken as 0.7 times the component and cladding (ASD) loads obtained from Table R301.2(2).
  2. For cantilever members, L shall be taken as twice the length of the cantilever.
  3. For aluminum structural members or panels used in roofs or walls of sunroom additions or patio covers, not supporting edge of glass or sandwich panels, the total load deflection shall not exceed L/60. For continuous aluminum structural members supporting edge of glass, the total load deflection shall not exceed L/175 for each glass lite or L/60 for the entire length of the member, whichever is more stringent. For sandwich panels used in roofs or walls of sunroom additions or patio covers, the total load deflection shall not exceed L/120.
  4. Deflection for exterior walls with interior gypsum board finish shall be limited to an allowable deflection of H/180.
  5. Refer to Section R703.8.2.

R301.8 Nominal Sizes

For the purposes of this code, dimensions of lumber specified shall be deemed to be nominal dimensions unless specifically designated as actual dimensions.

R301.9

All exterior wall coverings and soffits shall be capable of resisting the design pressures specified for walls for components and cladding loads in accordance with Table R301.2(2) as modified by Table R301.2(3). Manufactured soffits shall be tested at 1.5 times the design pressure.

Section R302 Fire-Resistant Construction

R302.1 Exterior Walls

Construction, projections, openings and penetrations of exterior walls of dwellings and accessory buildings shall comply with Table R302.1.
Exceptions:
  1. Walls, projections, openings or penetrations in walls perpendicular to the line used to determine the fire separation distance.
  2. Walls of individual dwelling units and their accessory structures located on the same lot.
  3. Detached tool sheds and storage sheds, playhouses and similar structures exempted from permits are not required to provide wall protection based on location on the lot. Projections beyond the exterior wall shall not extend over the lot line.
  4. Detached garages accessory to a dwelling located within 2 feet (610 mm) of a lot line are permitted to have roof eave projections not exceeding 4 inches (102 mm).
  5. Foundation vents installed in compliance with this code are permitted.
  6. Screen enclosure walls of insect screening with a maximum of 25-percent solid flexible finishes.
  7. For zero lot line developments where permitted by local regulations, openings and roof overhang projections shall be permitted on the exterior wall of a building located on a zero lot line when the building exterior wall is separated from an adjacent building exterior wall by a distance of 6 feet or more, and the roof overhang projection is separated from an adjacent building projection by a distance of 4 feet or more, with 1-hour fire-resistive construction on the underside of the overhang required, unless the separation between projections is 6 feet or more.
TABLE R302.1
EXTERIOR WALLS
EXTERIOR WALL ELEMENT MINIMUM
FIRE-RESISTANCE RATING
 MINIMUM FIRE
SEPARATION DISTANCE
Walls Fire-resistance rated 1 hour—tested in accordance with ASTM E119 or UL 263 with exposure from the
outside or calculated per Florida Building Code, Building
 0 feet
Not fire-resistance rated 0 hours 3 feeta
Projections Not allowed N/A < 2 feet
Fire-resistance rated 1 hour on the underside, or heavy timber, or fire-
retardant-treated woodb, c
 2 feeta
Not fire-resistance rated 0 hours 3 feet
Openings in walls Not allowed N/A < 3 feet
Unlimited 0 hours 3 feeta
Penetrations All Comply with Section R302.4 < 3 feet
None required 3 feeta
For SI: 1 foot = 304.8 mm.
N/A = Not Applicable.
  1. For residential subdivisions where all dwellings are equipped throughout with an automatic sprinkler system installed in accordance with Section P2904, the fire separation distance for nonrated exterior walls and rated projections shall be permitted to be reduced to 0 feet, and unlimited unprotected openings and penetrations shall be permitted, where the adjoining lot provides an open setback yard that is 6 feet or more in width on the opposite side of the property line.
  2. The roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave if fireblocking is provided from the wall top plate to the underside of the roof sheathing.
  3. The roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave provided that gable vent openings are not installed.
Table R302.1(1)
Reserved.
Table R302.1(2)
Exterior Walls—Dwellings with Fire Sprinklers.
Reserved.
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R302.2 Townhouses

Each townhouse shall be considered a separate building and shall be separated by separate fire-resistance rated exterior wall assemblies meeting the requirements of zero clearance from property lines of Section R302.1 for exterior walls.
Exception: A common 2-hour fire-resistance-rated wall assembly tested in accordance with ASTM E119, UL 263, or in accordance with the Florida Building Code, Building Section 722 is permitted for townhouses if such walls do not contain plumbing or mechanical equipment, ducts or vents in the cavity of the common wall unless such materials and methods of penetration comply with Section R302.4. The wall shall be rated for fire exposure from both sides and shall extend to and be tight against exterior walls and the underside of the roof sheathing. Electrical installations shall be installed in accordance with Chapter 34. Penetrations of electrical outlet boxes shall be in accordance with Section R302.4.
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R302.2.1 Continuity

The fire-resistance-rated wall or assembly separating townhouses shall be continuous from the foundation to the underside of the roof sheathing, deck or slab. The fire-resistance rating shall extend the full length of the wall or assembly, including wall extensions through and separating attached enclosed accessory structures.
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R302.2.2 Parapets for Townhouses

Parapets constructed in accordance with Section R302.2.3 shall be constructed for townhouses as an extension of exterior walls or common walls in accordance with the following:
  1. Where roof surfaces adjacent to the wall or walls are at the same elevation, the parapet shall extend not less than 30 inches (762 mm) above the roof surfaces.
  2. Where roof surfaces adjacent to the wall or walls are at different elevations and the higher roof is not more than 30 inches (762 mm) above the lower roof, the parapet shall extend not less than 30 inches (762 mm) above the lower roof surface.
    Exception: A parapet is not required in the preceding two cases where the roof covering complies with a minimum Class C rating as tested in accordance with ASTM E108 or UL 790 and the roof decking or sheathing is of noncombustible materials or approved fire-retardant-treated wood for a distance of 4 feet (1219 mm) on each side of the wall or walls, or one layer of 5/8-inch (15.9 mm) Type X gypsum board is installed directly beneath the roof decking or sheathing, supported by not less than nominal 2-inch (51 mm) ledgers attached to the sides of the roof framing members, for a distance of not less than 4 feet (1219 mm) on each side of the wall or walls and any openings or penetrations in the roof are not within 4 feet (1219 mm) of the common walls.
  3. A parapet is not required where roof surfaces adjacent to the wall or walls are at different elevations and the higher roof is more than 30 inches (762 mm) above the lower roof. The common wall construction from the lower roof to the underside of the higher roof deck shall have not less than a 1-hour fire-resistance rating. The wall shall be rated for exposure from both sides.

R302.2.3 Parapet Construction

Parapets shall have the same fire-resistance rating as that required for the supporting wall or walls. On any side adjacent to a roof surface, the parapet shall have noncombustible faces for the uppermost 18 inches (457 mm), to include counterflashing and coping materials. Where the roof slopes toward a parapet at slopes greater than 2 units vertical in 12 units horizontal (16.7-percent slope), the parapet shall extend to the same height as any portion of the roof within a distance of 3 feet (914 mm), and the height shall be not less than 30 inches (762 mm).

R302.2.4 Structural Independence

Each individual townhouse shall be structurally independent.
Exceptions:
  1. Foundations supporting exterior walls or common walls.
  2. Structural roof and wall sheathing from each unit fastened to the common wall framing.
  3. Nonstructural wall and roof coverings.
  4. Flashing at termination of roof covering over common wall.

R302.3 Two-Family Dwellings

Dwelling units in two-family dwellings shall be separated from each other by wall and floor assemblies having not less than a 1-hour fire-resistance rating where tested in accordance with ASTM E119, UL 263 or Section 703.3 of the Florida Building Code, Building. Fire-resistance-rated floor/ceiling and wall assemblies shall extend to and be tight against the exterior wall, and wall assemblies shall extend from the foundation to the underside of the roof sheathing.
Exceptions:
  1. A fire-resistance rating of 1/2 hour shall be permitted in buildings equipped throughout with an automatic sprinkler system installed in accordance with NFPA 13.
  2. Wall assemblies need not extend through attic spaces where the ceiling is protected by not less than 5/8-inch (15.9 mm) Type X gypsum board, an attic draft stop constructed as specified in Section R302.12.1 is provided above and along the wall assembly separating the dwellings and the structural framing supporting the ceiling is protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent.
  3. Screen enclosure walls of insect screening with a maximum of 25-percent solid flexible finishes.
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R302.3.1 Supporting Construction

Where floor assemblies are required to be fire-resistance rated by Section R302.3, the supporting construction of such assemblies shall have an equal or greater fire-resistance rating.
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R302.4 Dwelling Unit Rated Penetrations

Penetrations of wall or floor-ceiling assemblies required to be fire-resistance rated in accordance with Section R302.2 or R302.3 shall be protected in accordance with this section.
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R302.4.1 Through Penetrations

Through penetrations of fire-resistance-rated wall or floor assemblies shall comply with Section R302.4.1.1 or R302.4.1.2.
Exception: Where the penetrating items are steel, ferrous or copper pipes, tubes or conduits, the annular space shall be protected as follows:
  1. In concrete or masonry wall or floor assemblies, concrete, grout or mortar shall be permitted where installed to the full thickness of the wall or floor assembly or the thickness required to maintain the fire-resistance rating, provided that both of the following are complied with:
    1. 1.1. The nominal diameter of the penetrating item is not more than 6 inches (152 mm).
    2. 1.2. The area of the opening through the wall does not exceed 144 square inches (92 900 mm2).
  2. The material used to fill the annular space shall prevent the passage of flame and hot gases sufficient to ignite cotton waste where subjected to ASTM E119 or UL 263 time temperature fire conditions under a positive pressure differential of not less than 0.01 inch of water (3 Pa) at the location of the penetration for the time period equivalent to the fire-resistance rating of the construction penetrated.
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R302.4.1.1 Fire-Resistance-Rated Assembly

Penetrations shall be installed as tested in the approved fire-resistance-rated assembly.

R302.4.1.2 Penetration Firestop System

Penetrations shall be protected by an approved penetration firestop system installed as tested in accordance with ASTM E814 or UL 1479, with a positive pressure differential of not less than 0.01 inch of water (3 Pa) and shall have an F rating of not less than the required fire-resistance rating of the wall or floor-ceiling assembly penetrated.

R302.4.2 Membrane Penetrations

Membrane penetrations shall comply with Section R302.4.1. Where walls are required to have a fire-resistance rating, recessed fixtures shall be installed so that the required fire-resistance rating will not be reduced.
Exceptions:
  1. Membrane penetrations of not more than 2-hour fire-resistance-rated walls and partitions by steel electrical boxes that do not exceed 16 square inches (0.0103 m2) in area provided that the aggregate area of the openings through the membrane does not exceed 100 square inches (0.0645 m2) in any 100 square feet (9.29 m2) of wall area. The annular space between the wall membrane and the box shall not exceed 1/8 inch (3.1 mm). Such boxes on opposite sides of the wall shall be separated by one of the following:
    1. 1.1. By a horizontal distance of not less than 24 inches (610 mm) where the wall or partition is constructed with individual noncommunicating stud cavities.
    2. 1.2. By a horizontal distance of not less than the depth of the wall cavity where the wall cavity is filled with cellulose loose-fill, rockwool or slag mineral wool insulation.
    3. 1.3. By solid fireblocking in accordance with Section R302.11.
    4. 1.4. By protecting both boxes with listed putty pads.
    5. 1.5. By other listed materials and methods.
  2. Membrane penetrations by listed electrical boxes of any materials provided that the boxes have been tested for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing. The annular space between the wall membrane and the box shall not exceed 1/8 inch (3.1 mm) unless listed otherwise. Such boxes on opposite sides of the wall shall be separated by one of the following:
    1. 2.1. By the horizontal distance specified in the listing of the electrical boxes.
    2. 2.2. By solid fireblocking in accordance with Section R302.11.
    3. 2.3. By protecting both boxes with listed putty pads.
    4. 2.4. By other listed materials and methods.
  3. The annular space created by the penetration of a fire sprinkler provided that it is covered by a metal escutcheon plate.
  4. Ceiling membrane penetrations by listed luminaires or by luminaires protected with listed materials that have been tested for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing.
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R302.5 Dwelling-Garage Opening and Penetration Protection

Openings and penetrations through the walls or ceilings separating the dwelling from the garage shall be in accordance with Sections R302.5.1 through R302.5.3.
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R302.5.1 Opening Protection

Openings from a private garage directly into a room used for sleeping purposes shall not be permitted. Other openings between the garage and residence shall be equipped with solid wood doors not less than 13/8 inches (35 mm) in thickness, solid or honeycombcore steel doors not less than 13/8 inches (35 mm) thick, or 20-minute fire-rated doors.

R302.5.2 Duct Penetration

Ducts in the garage and ducts penetrating the walls or ceilings separating the dwelling from the garage shall be constructed of a minimum No. 26 gage (0.48 mm) sheet steel, 1 inch (25.4 mm) minimum rigid nonmetallic Class 0 or Class 1 duct board, or other approved material and shall not have openings into the garage.

R302.5.3 Other Penetrations

Penetrations through the separation required in Section R302.6 shall be protected as required by Section R302.11, Item 4.

R302.6 Dwelling-Garage Fire Separation

The garage shall be separated as required by Table R302.6. Openings in garage walls shall comply with Section R302.5. Attachment of gypsum board shall comply with Table R702.3.5. The wall separation provisions of Table R302.6 shall not apply to garage walls that are perpendicular to the adjacent dwelling unit wall.
TABLE R302.6
DWELLING-GARAGE SEPARATION
SEPARATION MATERIAL
From the residence and attics Not less than 1/2-inch gypsum board or equivalent applied to the
garage side
From habitable rooms above the garage Not less than 5/8-inch Type X gypsum board or equivalent
Structure(s) supporting floor/ceiling assemblies used for separation
required by this section
 Not less than 1/2-inch gypsum board or equivalent
Garages located less than 3 feet from a dwelling unit on the same lot Not less than 1/2-inch gypsum board or equivalent applied to the interior
side of exterior walls that are within this area
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
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R302.7 Under-Stair Protection

Enclosed space under stairs that is accessed by a door or access panel shall have walls, under-stair surface and any soffits protected on the enclosed side with 1/2-inch (12.7 mm) gypsum board.

R302.8 Foam Plastics

For requirements for foam plastics, see Section R316.

R302.9 Flame Spread Index and Smoke-Developed Index for Wall and Ceiling Finishes

Flame spread and smoke-developed indexes for wall and ceiling finishes shall be in accordance with Sections R302.9.1 through R302.9.4.

R302.9.1 Flame Spread Index

Wall and ceiling finishes shall have a flame spread index of not greater than 200.
Exception: Flame spread index requirements for finishes shall not apply to trim defined as picture molds, chair rails, baseboards and handrails; to doors and windows or their frames; or to materials that are less than 1/28 inch (0.91 mm) in thickness cemented to the surface of walls or ceilings if these materials exhibit flame spread index values not greater than those of paper of this thickness cemented to a noncombustible backing.

R302.9.2 Smoke-Developed Index

Wall and ceiling finishes shall have a smoke-developed index of not greater than 450.

R302.9.3 Testing

Tests shall be made in accordance with ASTM E84 or UL 723.

R302.9.4 Alternative Test Method

As an alternative to having a flame spread index of not greater than 200 and a smoke-developed index of not greater than 450 where tested in accordance with ASTM E84 or UL 723, wall and ceiling finishes shall be permitted to be tested in accordance with NFPA 286. Materials tested in accordance with NFPA 286 shall meet the following criteria:
The interior finish shall comply with the following:
  1. During the 40 kW exposure, flames shall not spread to the ceiling.
  2. The flame shall not spread to the outer extremity of the sample on any wall or ceiling.
  3. Flashover, as defined in NFPA 286, shall not occur.
  4. The peak heat release rate throughout the test shall not exceed 800 kW.
  5. The total smoke released throughout the test shall not exceed 1,000 m2.

R302.10 Flame Spread Index and Smoke-Developed Index for Insulation

Flame spread and smoke-developed index for insulation shall be in accordance with Sections R302.10.1 through R302.10.5.

R302.10.1 Insulation

Insulating materials installed within floor-ceiling assemblies, roof-ceiling assemblies, wall assemblies, crawl spaces and attics shall comply with the requirements of this section. They shall exhibit a flame spread index not to exceed 25 and a smoke-developed index not to exceed 450 where tested in accordance with ASTM E84 or UL 723. Insulating materials, where tested in accordance with the requirements of this section, shall include facings, where used, such as vapor retarders, vapor-permeable membranes and similar coverings.
Exceptions:
  1. Where such materials are installed in concealed spaces, the flame spread index and smoke-developed index limitations do not apply to the facings, provided that the facing is installed in substantial contact with the unexposed surface of the ceiling, floor or wall finish.
  2. Cellulose fiber loose-fill insulation, that is not spray applied, complying with the requirements of Section R302.10.3, shall not be required to meet a flame spread index requirement but shall be required to meet a smoke-developed index of not more than 450 where tested in accordance with CAN/ULC S102.2.
  3. Foam plastic insulation shall comply with Section R316.

R302.10.2 Loose-Fill Insulation

Loose-fill insulation materials that cannot be mounted in the ASTM E84 or UL 723 apparatus without a screen or artificial supports shall comply with the flame spread and smoke-developed limits of Section R302.10.1 where tested in accordance with CAN/ULC S102.2.
Exception: Cellulosic fiber loose-fill insulation shall not be required to be tested in accordance with CAN/ULC S102.2, provided such insulation complies with the requirements of Sections R302.10.1 and R302.10.3.

R302.10.3 Cellulosic Fiber Loose-Fill Insulation

Cellulosic fiber loose-fill insulation shall comply with CPSC 16 CFR, Parts 1209 and 1404. Each package of such insulating material shall be clearly labeled in accordance with CPSC 16 CFR, Parts 1209 and 1404.

R302.10.4 Exposed Attic Insulation

Exposed insulation materials installed on attic floors shall have a critical radiant flux not less than 0.12 watt per square centimeter.

R302.10.5 Testing

Tests for critical radiant flux shall be made in accordance with ASTM E970.

R302.11 Fireblocking

In combustible construction, fireblocking shall be provided to cut off both vertical and horizontal concealed draft openings and to form an effective fire barrier between stories, and between a top story and the roof space.
Fireblocking shall be provided in wood-framed construction in the following locations:
  1. In concealed spaces of stud walls and partitions, including furred spaces and parallel rows of studs or staggered studs, as follows:
    1. 1.1. Vertically at the ceiling and floor levels.
    2. 1.2. Horizontally at intervals not exceeding 10 feet (3048 mm).
  2. At interconnections between concealed vertical and horizontal spaces such as occur at soffits, drop ceilings and cove ceilings.
  3. In concealed spaces between stair stringers at the top and bottom of the run. Enclosed spaces under stairs shall comply with Section R302.7.
  4. At openings around vents, pipes, ducts, cables and wires at ceiling and floor level, with an approved material to resist the free passage of flame and products of combustion. The material filling this annular space shall not be required to meet the ASTM E136 requirements.
  5. For the fireblocking of chimneys and fireplaces, see Section R1003.19.
  6. Fireblocking of cornices of a two-family dwelling is required at the line of dwelling unit separation.
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R302.11.1 Fireblocking Materials

Except as provided in Section R302.11, Item 4, fireblocking shall consist of the following materials.
  1. Two-inch (51 mm) nominal lumber.
  2. Two thicknesses of 1-inch (25.4 mm) nominal lumber with broken lap joints.
  3. One thickness of 23/32-inch (18.3 mm) wood structural panels with joints backed by 23/32-inch (18.3 mm) wood structural panels.
  4. One thickness of 3/4-inch (19.1 mm) particleboard with joints backed by 3/4-inch (19.1 mm) particleboard.
  5. One-half-inch (12.7 mm) gypsum board.
  6. One-quarter-inch (6.4 mm) cement-based millboard.
  7. Batts or blankets of mineral wool or glass fiber or other approved materials installed in such a manner as to be securely retained in place.
  8. Cellulose insulation installed as tested in accordance with ASTM E119 or UL 263, for the specific application.

R302.11.1.1 Batts or Blankets of Mineral or Glass Fiber

Batts or blankets of mineral or glass fiber or other approved nonrigid materials shall be permitted for compliance with the 10-foot (3048 mm) horizontal fireblocking in walls constructed using parallel rows of studs or staggered studs.

R302.11.1.2 Unfaced Fiberglass

Unfaced fiberglass batt insulation used as fireblocking shall fill the entire cross section of the wall cavity to a height of not less than 16 inches (406 mm) measured vertically. Where piping, conduit or similar obstructions are encountered, the insulation shall be packed tightly around the obstruction.

R302.11.1.3 Loose-Fill Insulation Material

Loose-fill insulation material shall not be used as a fireblock unless specifically tested in the form and manner intended for use to demonstrate its ability to remain in place and to retard the spread of fire and hot gases.

R302.11.2 Fireblocking Integrity

The integrity of fireblocks shall be maintained.

R302.12 Draftstopping

In combustible construction where there is usable space both above and below the concealed space of a floor-ceiling assembly, draftstops shall be installed so that the area of the concealed space does not exceed 1,000 square feet (92.9 m2). Draftstopping shall divide the concealed space into approximately equal areas. Where the assembly is enclosed by a floor membrane above and a ceiling membrane below, draftstopping shall be provided in floor-ceiling assemblies under the following circumstances:
  1. Ceiling is suspended under the floor framing.
  2. Floor framing is constructed of truss-type open-web or perforated members.
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R302.12.1 Materials

Draftstopping materials shall be not less than 1/2-inch (12.7 mm) gypsum board, 3/8-inch (9.5 mm) wood structural panels or other approved materials adequately supported. Draftstopping shall be installed parallel to the floor framing members unless otherwise approved by the building official. The integrity of the draftstops shall be maintained.
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R302.13 Fire Protection of Floors

Floor assemblies that are not required elsewhere in this code to be fire-resistance rated, shall be provided with a 1/2-inch (12.7 mm) gypsum wallboard membrane, 5/8-inch (16 mm) wood structural panel membrane, or equivalent on the underside of the floor framing member. Penetrations or openings for ducts, vents, electrical outlets, lighting, devices, luminaires, wires, speakers, drainage, piping and similar openings or penetrations shall be permitted.
Exceptions:
  1. Floor assemblies located directly over a space protected by an automatic sprinkler system in accordance with Section P2904, NFPA 13D, or other approved equivalent sprinkler system.
  2. Floor assemblies located directly over a crawl space not intended for storage or fuel-fired appliances.
  3. Portions of floor assemblies shall be permitted to be unprotected where complying with the following:
    1. 3.1. The aggregate area of the unprotected portions does not exceed 80 square feet (7.4 m2) per story.
    2. 3.2. Fireblocking in accordance with Section R302.11.1 is installed along the perimeter of the unprotected portion to separate the unprotected portion from the remainder of the floor assembly.
  4. Wood floor assemblies using dimension lumber or structural composite lumber equal to or greater than 2-inch by 10-inch (50.8 mm by 254 mm) nominal dimension, or other approved floor assemblies demonstrating equivalent fire performance.

R302.14 Combustible Insulation Clearance

Combustible insulation shall be separated not less than 3 inches (76 mm) from recessed luminaires, fan motors and other heat-producing devices.
Exception: Where heat-producing devices are listed for lesser clearances, combustible insulation complying with the listing requirements shall be separated in accordance with the conditions stipulated in the listing.
Recessed luminaires installed in the building thermal envelope shall meet the requirements of the Florida Building Code, Energy Conservation.

Section R303 Light, Ventilation and Heating

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R303.1 Habitable Rooms

Habitable rooms shall have an aggregate glazing area of not less than 8 percent of the floor area of such rooms. Natural ventilation shall be through windows, skylights, doors, louvers or other approved openings to the outdoor air. Such openings shall be provided with ready access or shall otherwise be readily controllable by the building occupants. The openable area to the outdoors shall be not less than 4 percent of the floor area being ventilated.
Exceptions:
  1. The glazed areas need not be openable where the opening is not required by Section R310 and a whole-house mechanical ventilation system is installed in accordance with Section M1507.
  2. The glazed areas need not be installed in rooms where Exception 1 is satisfied and artificial light is provided that is capable of producing an average illumination of 6 footcandles (65 lux) over the area of the room at a height of 30 inches (762 mm) above the floor level.
  3. Use of sunroom and patio covers, as defined in Section R202, shall be permitted for natural ventilation if in excess of 40 percent of the exterior sunroom walls are open, or are enclosed only by insect screening.
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R303.2 Adjoining Rooms

For the purpose of determining light and ventilation requirements, any room shall be considered to be a portion of an adjoining room where not less than one-half of the area of the common wall is open and unobstructed and provides an opening of not less than one-tenth of the floor area of the interior room and not less than 25 square feet (2.3 m2).
Exception: Openings required for light or ventilation shall be permitted to open into a sunroom with thermal isolation or a patio cover, provided that there is an openable area between the adjoining room and the sunroom or patio cover of not less than one-tenth of the floor area of the interior room and not less than 20 square feet (2 m2). The minimum openable area to the outdoors shall be based upon the total floor area being ventilated.
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R303.3 Bathrooms

Bathrooms, water closet compartments and other similar rooms shall be provided with aggregate glazing area in windows of not less than 3 square feet (0.3 m2), one-half of which must be openable.
Exception: The glazed areas shall not be required where artificial light and a local exhaust system are provided. The minimum local exhaust rates shall be determined in accordance with Section M1507. Exhaust air from the space shall be exhausted directly to the outdoors.

R303.4 Mechanical Ventilation

Where the air infiltration rate of a dwelling unit is less than 3.00 air changes per hour where tested with a blower door at a pressure of 0.2 inch w.c. (50 Pa) in accordance with Section R402.4.1.2 of the Florida Building Code, Energy Conservation, the dwelling unit shall be provided with whole-house mechanical ventilation in accordance with Section M1507.3.

R303.5 Opening Location

Outdoor intake and exhaust openings shall be located in accordance with Sections R303.5.1 and R303.5.2.

R303.5.1 Intake Openings

Mechanical and gravity outdoor air intake openings shall be located not less than 10 feet (3048 mm) from any hazardous or noxious contaminant, such as vents, chimneys, plumbing vents, streets, alleys, parking lots and loading docks.
For the purpose of this section, the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious.
Exceptions:
  1. The 10-foot (3048 mm) separation is not required where the intake opening is located 3 feet (914 mm) or greater below the contaminant source.
  2. Vents and chimneys serving fuel-burning appliances shall be terminated in accordance with the applicable provisions of Chapters 18 and 24.
  3. Clothes dryer exhaust ducts shall be terminated in accordance with Section M1502.3.
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R303.5.2 Exhaust Openings

Exhaust air shall not be directed onto walkways.

R303.6 Outside Opening Protection

Air exhaust and intake openings that terminate outdoors shall be protected with corrosion-resistant screens, louvers or grilles having an opening size of not less than 1/4 inch (6 mm) and a maximum opening size of 1/2 inch (13 mm), in any dimension. Openings shall be protected against local weather conditions. Outdoor air exhaust and intake openings shall meet the provisions for exterior wall opening protectives in accordance with this code.

R303.7 Interior Stairway Illumination

Interior stairways shall be provided with an artificial light source to illuminate the landings and treads. The light source shall be capable of illuminating treads and landings to levels of not less than 1 footcandle (11 lux) as measured at the center of treads and landings. There shall be a wall switch at each floor level to control the light source where the stairway has six or more risers.
Exception: A switch is not required where remote, central or automatic control of lighting is provided.
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R303.8 Exterior Stairway Illumination

Exterior stairways shall be provided with an artificial light source located at the top landing of the stairway. Exterior stairways providing access to a basement from the outdoor grade level shall be provided with an artificial light source located at the bottom landing of the stairway.
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R303.9 Required Glazed Openings

Required glazed openings shall open directly onto a street or public alley, or a yard or court located on the same lot as the building.
Exceptions:
  1. Required glazed openings that face into a roofed porch where the porch abuts a street, yard or court and the longer side of the porch is not less than 65 percent unobstructed and the ceiling height is not less than 7 feet (2134 mm).
  2. Eave projections shall not be considered as obstructing the clear open space of a yard or court.
  3. Required glazed openings that face into the area under a deck, balcony, bay or floor cantilever where a clear vertical space not less than 36 inches (914 mm) in height is provided.

R303.9.1 Sunroom Additions

Required glazed openings shall be permitted to open into sunroom additions or patio covers that abut a street, yard or court if in excess of 40 percent of the exterior sunroom walls are open, or are enclosed only by insect screening, and the ceiling height of the sunroom is not less than 7 feet (2134 mm).

R303.10 Required Heating

Where the winter design temperature in Table R301.2(1) is below 60°F (16°C), every dwelling unit shall be provided with heating facilities capable of maintaining a room temperature of not less than 68°F (20°C) at a point 3 feet (914 mm) above the floor and 2 feet (610 mm) from exterior walls in habitable rooms at the design temperature. The installation of one or more portable space heaters shall not be used to achieve compliance with this section.
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Section R304 Minimum Room Areas

R304.1 Minimum Area

Habitable rooms shall have a floor area of not less than 70 square feet (6.5 m2).
Exception: Kitchens.

R304.2 Minimum Dimensions

Habitable rooms shall be not less than 7 feet (2134 mm) in any horizontal dimension.
Exception: Kitchens.

R304.3 Height Effect on Room Area

Portions of a room with a sloping ceiling measuring less than 5 feet (1524 mm) or a furred ceiling measuring less than 7 feet (2134 mm) from the finished floor to the finished ceiling shall not be considered as contributing to the minimum required habitable area for that room.
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Section R305 Ceiling Height

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R305.1 Minimum Height

Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
Exceptions:
  1. For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).
  2. The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.
  3. Beams, girders, ducts or other obstructions in basements containing habitable space shall be permitted to project to within 6 feet 4 inches (1931 mm) of the finished floor.
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R305.1.1 Basements

Portions of basements that do not contain habitable space or hallways shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
Exception: At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1931 mm) from the finished floor.

Section R306 Sanitation

R306.1 Toilet Facilities

Every dwelling unit shall be provided with a water closet, lavatory, and a bathtub or shower.

R306.2 Kitchen

Each dwelling unit shall be provided with a kitchen area and every kitchen area shall be provided with a sink.
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R306.3 Sewage Disposal

Plumbing fixtures shall be connected to a sanitary sewer or to an approved private sewage disposal system in accordance with Chapter 64E-6, Florida Administrative Code, Standards for Onsite Sewage Treatment and Disposal Systems.

R306.4 Water Supply to Fixtures

Plumbing fixtures shall be connected to an approved water supply. Kitchen sinks, lavatories, bathtubs, showers, bidets, laundry tubs and washing machine outlets shall be provided with hot and cold water.
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Section R307 Toilet, Bath and Shower Spaces

R307.1 Space Required

Fixtures shall be spaced in accordance with Figure R307.1, and in accordance with the requirements of Section P2705.1.
For SI: 1 inch = 25.4 mm.
FIGURE R307.1
MINIMUM FIXTURE CLEARANCES
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R307.2 Bathtub and Shower Spaces

Bathtub and shower floors and walls above bathtubs with installed shower heads and in shower compartments shall be finished with a nonabsorbent surface. Such wall surfaces shall extend to a height of not less than 6 feet (1829 mm) above the floor.
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Section R308 Glazing

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R308.1 Identification

Except as indicated in Section R308.1.1 each pane of glazing installed in hazardous locations as defined in Section R308.4 shall be provided with a manufacturer's designation specifying who applied the designation, designating the type of glass and the safety glazing standard with which it complies, which is visible in the final installation. The designation shall be acid etched, sandblasted, ceramic-fired, laser etched, embossed, or be of a type that once applied cannot be removed without being destroyed. A label shall be permitted in lieu of the manufacturer's designation.
Exceptions:
  1. For other than tempered glass, manufacturer's designations are not required provided that the building official approves the use of a certificate, affidavit or other evidence confirming compliance with this code.
  2. Tempered spandrel glass is permitted to be identified by the manufacturer with a removable paper designation.

R308.1.1 Identification of Multiple Assemblies

Multipane assemblies having individual panes not exceeding 1 square foot (0.09 m2) in exposed area shall have not less than one pane in the assembly identified in accordance with Section R308.1. Other panes in the assembly shall be labeled "CPSC 16 CFR 1201" or "ANSI Z97.1" as appropriate.

R308.2 Louvered Windows or Jalousies

Regular, float, wired or patterned glass in jalousies and louvered windows shall be not less than nominal 3/16 inch (5 mm) thick and not more than 48 inches (1219 mm) in length. Exposed glass edges shall be smooth.

R308.2.1 Wired Glass Prohibited

Wired glass with wire exposed on longitudinal edges shall not be used in jalousies or louvered windows.

R308.3 Human Impact Loads

Individual glazed areas, including glass mirrors in hazardous locations such as those indicated as defined in Section R308.4, shall pass the test requirements of Section R308.3.1.
Exceptions:
  1. Louvered windows and jalousies shall comply with Section R308.2.
  2. Mirrors and other glass panels mounted or hung on a surface that provides a continuous backing support.
  3. Glass unit masonry complying with Section R607.

R308.3.1 Impact Test

Where required by other sections of the code, glazing shall be tested in accordance with CPSC 16 CFR 1201. Glazing shall comply with the test criteria for Category II unless otherwise indicated in Table R308.3.1(1).
Exception: Glazing not in doors or enclosures for hot tubs, whirlpools, saunas, steam rooms, bathtubs and showers shall be permitted to be tested in accordance with ANSI Z97.1. Glazing shall comply with the test criteria for Class A unless indicated in Table R308.3.1(2).
TABLE R308.3.1(1)
MINIMUM CATEGORY CLASSIFICATION OF GLAZING USING CPSC 16 CFR 1201
EXPOSED SURFACE
AREA OF ONE SIDE
OF ONE LITE		 GLAZING IN
STORM OR
COMBINATION
DOORS
(Category Class)		 GLAZING IN
DOORS
(Category Class)		 GLAZED PANELS
REGULATED BY
SECTION R308.4.3
(Category Class)
 GLAZED PANELS
REGULATED BY
SECTION R308.4.2
(Category Class)
 GLAZING IN
DOORS AND
ENCLOSURES
REGULATED BY
SECTION 308.4.5
(Category Class)
 SLIDING GLASS
DOORS PATIO TYPE
(Category Class)
9 square feet or less I I NR I II II
More than 9 square feet II II II II II II
For SI: 1 square foot = 0.0929 m2.
NR = "No Requirement."
TABLE R308.3.1(2)
MINIMUM CATEGORY CLASSIFICATION OF GLAZING USING ANSI Z97.1
EXPOSED SURFACE AREA
OF ONE SIDE OF ONE LITE
 GLAZED PANELS REGULATED BY
(Category Class)
 GLAZED PANELS REGULATED BY
(Category Class)
 DOORS AND ENCLOSURES REGULATED
(Category Class)
9 square feet or less No requirement B A
More than 9 square feet A A A
For SI: 1 square foot = 0.0929 m2.
  1. Use is permitted only by the exception to Section R308.3.1.

R308.4 Hazardous Locations

The locations specified in Sections R308.4.1 through R308.4.7 shall be considered to be specific hazardous locations for the purposes of glazing.
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R308.4.1 Glazing in Doors

Glazing in fixed and operable panels of swinging, sliding and bifold doors shall be considered to be a hazardous location.
Exceptions:
  1. Glazed openings of a size through which a 3-inch-diameter (76 mm) sphere is unable to pass.
  2. Decorative glazing.

R308.4.2 Glazing Adjacent to Doors

Glazing in an individual fixed or operable panel adjacent to a door shall be considered to be a hazardous location where the bottom exposed edge of the glazing is less than 60 inches (1524 mm) above the floor or walking surface and it meets either of the following conditions:
  1. Where the glazing is within 24 inches (610 mm) of either side of the door in the plane of the door in a closed position.
  2. Where the glazing is on a wall less than 180 degrees from the plane of the door in a closed position and within 24 inches (610 mm) of the hinge side of an in-swinging door.
Exceptions:
  1. Decorative glazing.
  2. Where there is an intervening wall or other permanent barrier between the door and the glazing.
  3. Where access through the door is to a closet or storage area 3 feet (914 mm) or less in depth. Glazing in this application shall comply with Section R308.4.3.
  4. Glazing that is adjacent to the fixed panel of patio doors.
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R308.4.3 Glazing in Windows

Glazing in an individual fixed or operable panel that meets all of the following conditions shall be considered to be a hazardous location:
  1. The exposed area of an individual pane is larger than 9 square feet (0.836 m2),
  2. The bottom edge of the glazing is less than 18 inches (457 mm) above the floor,
  3. The top edge of the glazing is more than 36 inches (914 mm) above the floor; and
  4. One or more walking surfaces are within 36 inches (914 mm), measured horizontally and in a straight line, of the glazing.
    Exceptions:
    1. Decorative glazing.
    2. Where glazing is adjacent to a walking surface and a horizontal rail is installed 34 to 38 inches (864 to 965 mm) above the walking surface. The rail shall be capable of withstanding a horizontal load of 50 pounds per linear foot (730 N/m) without contacting the glass and have a cross-sectional height of not less than 11/2 inches (38 mm).
    3. Outboard panes in insulating glass units and other multiple glazed panels where the bottom edge of the glass is 25 feet (7620 mm) or more above grade, a roof, walking surfaces or other horizontal [within 45 degrees (0.79 rad) of horizontal] surface adjacent to the glass exterior.
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R308.4.4 Glazing in Guards and Railings

Glazing in guards and railings, including structural baluster panels and nonstructural in-fill panels, regardless of area or height above a walking surface shall be considered to be a hazardous location.

R308.4.5 Glazing and Wet Surfaces

Glazing in walls, enclosures or fences containing or facing hot tubs, spas, whirlpools, saunas, steam rooms, bathtubs, showers and indoor or outdoor swimming pools where the bottom exposed edge of the glazing is less than 60 inches (1524 mm) measured vertically above any standing or walking surface shall be considered to be a hazardous location. This shall apply to single glazing and each pane in multiple glazing.
Exception: Glazing that is more than 60 inches (1524 mm), measured horizontally and in a straight line, from the water's edge of a bathtub, hot tub, spa, whirlpool or swimming pool or from the edge of a shower, sauna or steam room.
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R308.4.6 Glazing Adjacent to Stairs and Ramps

Glazing where the bottom exposed edge of the glazing is less than 36 inches (914 mm) above the plane of the adjacent walking surface of stairways, landings between flights of stairs and ramps shall be considered to be a hazardous location.
Exceptions:
  1. Where glazing is adjacent to a walking surface and a horizontal rail is installed at 34 to 38 inches (864 to 965 mm) above the walking surface. The rail shall be capable of withstanding a horizontal load of 50 pounds per linear foot (730 N/m) without contacting the glass and have a cross-sectional height of not less than 11/2 inches (38 mm).
  2. Glazing 36 inches (914 mm) or more measured horizontally from the walking surface.
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R308.4.7 Glazing Adjacent to the Bottom Stair Landing

Glazing adjacent to the landing at the bottom of a stairway where the glazing is less than 36 inches (914 mm) above the landing and within a 60-inch (1524 mm) horizontal arc less than 180 degrees from the bottom tread nosing shall be considered to be a hazardous location. See Figure R308.4.7.
Exception: The glazing is protected by a guard complying with Section R312 and the plane of the glass is more than 18 inches (457 mm) from the guard.
FIGURE R308.4.7
HAZARDOUS GLAZING LOCATIONS AT BOTTOM STAIR LANDINGS

R308.5 Site-Built Windows

Site-built windows shall comply with Section 2404 of the Florida Building Code, Building.

R308.6 Skylights and Sloped Glazing

Skylights and sloped glazing shall comply with the following sections.

R308.6.1 Definitions

The following terms are defined in Chapter 2:
SKYLIGHT, UNIT.
SKYLIGHTS AND SLOPED GLAZING.
TUBULAR DAYLIGHTING DEVICE (TDD).

R308.6.2 Materials

The following types of glazing shall be permitted to be used:
  1. Laminated glass with not less than a 0.015-inch (0.38 mm) polyvinyl butyral interlayer for glass panes 16 square feet (1.5 m2) or less in area located such that the highest point of the glass is not more than 12 feet (3658 mm) above a walking surface; for higher or larger sizes, the interlayer thickness shall be not less than 0.030 inch (0.76 mm).
  2. Fully tempered glass.
  3. Heat-strengthened glass.
  4. Wired glass.
  5. Approved rigid plastics.

R308.6.3 Screens, General

For fully tempered or heat-strengthened glass, a broken-glass retention screen meeting the requirements of Section R308.6.7 shall be installed below the full area of the glass, except for fully tempered glass that meets condition 1 or 2 listed in Section R308.6.5.

R308.6.4 Screens With Multiple Glazing

Where the inboard pane is fully tempered, heat-strengthened or wired glass, a broken-glass retention screen meeting the requirements of Section R308.6.7 shall be installed below the full area of the glass, except for condition 1 or 2 listed in Section R308.6.5. Other panes in the multiple glazing shall be of any type listed in Section R308.6.2.

R308.6.5 Screens Not Required

Screens shall not be required where laminated glass complying with Item 1 of Section R308.6.2 is used as single glazing or the inboard pane in multiple glazing. Screens shall not be required where fully tempered glass is used as single glazing or the inboard pane in multiple glazing and either of the following conditions is met:
  1. Glass area 16 square feet (1.49 m2) or less. Highest point of glass not more than 12 feet (3658 mm) above a walking surface, nominal glass thickness not more than 3/16 inch (4.8 mm), and (for multiple glazing only) the other pane or panes fully tempered, laminated or wired glass.
  2. Glass area greater than 16 square feet (1.49 m2). Glass sloped 30 degrees (0.52 rad) or less from vertical, and highest point of glass not more than 10 feet (3048 mm) above a walking surface.

R308.6.6 Glass in Greenhouses

Any glazing material is permitted to be installed without screening in the sloped areas of greenhouses, provided that the greenhouse height at the ridge does not exceed 20 feet (6096 mm) above grade.

R308.6.7 Screen Characteristics

The screen and its fastenings shall be capable of supporting twice the weight of the glazing, be firmly and substantially fastened to the framing members, be installed within 4 inches (102 mm) of the glass and have a mesh opening of not more than 1 inch by 1 inch (25 mm by 25 mm).

R308.6.8 Curbs for Skylights

Unit skylights installed in a roof with a pitch flatter than three units vertical in 12 units horizontal (25-percent slope) shall be mounted on a curb extending not less than 4 inches (102 mm) above the plane of the roof unless otherwise specified in the manufacturer's installation instructions.

R308.6.9 Testing and Labeling

Unit skylights and tubular daylighting devices shall be tested by an approved independent laboratory, and bear a label identifying manufacturer, performance grade rating and approved inspection agency to indicate compliance with the requirements of AAMA/WDMA/CSA 101/I.S.2/A440.

R308.6.9.1 Comparative Analysis for Glass-Glazed Unit Skylights

Structural wind load design pressures for glass-glazed unit skylights different than the size tested in accordance with Section R308.6.9 shall be permitted to be different than the design value of the tested unit where determined in accordance with one of the following comparative analysis methods:
  1. Structural wind load design pressures for glass-glazed unit skylights smaller than the size tested in accordance with Section R308.6.9 shall be permitted to be higher than the design value of the tested unit provided that such higher pressures are determined by accepted engineering analysis. Components of the smaller unit shall be the same as those of the tested unit. Such calculated design pressures shall be validated by an additional test of the glass-glazed unit skylight having the highest allowable design pressure.
  2. In accordance with WDMA I.S. 11.

Section R309 Garages and Carports

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R309.1 Floor Surface

Garage floor surfaces shall be of approved noncombustible material.
The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.

R309.2 Carports

Carports shall be open on not less than two sides. Carport floor surfaces shall be of approved noncombustible material. Carports not open on two or more sides shall be considered to be a garage and shall comply with the provisions of this section for garages.
Exception: Asphalt surfaces shall be permitted at ground level in carports.
The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.
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R309.3 Flood Hazard Areas

For buildings located in flood hazard areas as established by Table R301.2(1), garage floors shall be:
  1. Elevated to or above the design flood elevation as determined in accordance with Section R322; or
  2. Located below the design flood elevation provided that the floors are at or above grade on not less than one side, are used solely for parking, building access or storage, meet the requirements of Section R322 and are otherwise constructed in accordance with this code.
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R309.4 Automatic Garage Door Openers

Automatic garage door openers, if provided, shall be listed and labeled in accordance with UL 325.

R309.5 Fire Sprinklers

Private garages shall be protected by fire sprinklers where the garage wall has been designed based on Table R302.1, Footnote a. Sprinklers in garages shall be connected to an automatic sprinkler system that complies with Section P2904. Garage sprinklers shall be residential sprinklers or quick-response sprinklers, designed to provide a density of 0.05 gpm/ft2. Garage doors shall not be considered obstructions with respect to sprinkler placement.

Section R310 Emergency Escape and Rescue Openings

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R310.1 Emergency Escape and Rescue Opening Required

Basements, habitable attics and every sleeping room shall have not less than one operable emergency escape and rescue opening. Where basements contain one or more sleeping rooms, an emergency escape and rescue opening shall be required in each sleeping room. Emergency escape and rescue openings shall open directly into a public way, or to a yard or court that opens to a public way.
Exceptions:
  1. Storm shelters and basements used only to house mechanical equipment not exceeding a total floor area of 200 square feet (18.58 m2).
  2. The emergency escape and rescue opening shall be permitted to open into a screen enclosure, open to the atmosphere, where a screen door is provided leading away from the residence.
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R310.1.1 Operational Constraints and Opening Control Devices

Emergency escape and rescue openings shall be operational from the inside of the room without the use of keys, tools or special knowledge. Window opening control devices complying with ASTM F2090 shall be permitted for use on windows serving as a required emergency escape and rescue opening.
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R310.2 Emergency Escape and Rescue Openings

Emergency escape and rescue openings shall have minimum dimensions as specified in this section.
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R310.2.1 Minimum Opening Area

Emergency and escape rescue openings shall have a net clear opening of not less than 5.7 square feet (0.530 m2). The net clear opening dimensions required by this section shall be obtained by the normal operation of the emergency escape and rescue opening from the inside. The net clear height opening shall be not less than 24 inches (610 mm) and the net clear width shall be not less than 20 inches (508 mm).
Exception: Grade floor or below grade openings shall have a net clear opening of not less than 5 square feet (0.465 m2).
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R310.2.2 Window Sill Height

Where a window is provided as the emergency escape and rescue opening, it shall have a sill height of not more than 44 inches (1118 mm) above the floor; where the sill height is below grade, it shall be provided with a window well in accordance with Section R310.2.3.
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R310.2.3 Window Wells

The horizontal area of the window well shall be not less than 9 square feet (0.9 m2), with a horizontal projection and width of not less than 36 inches (914 mm). The area of the window well shall allow the emergency escape and rescue opening to be fully opened.
Exception: The ladder or steps required by Section R310.2.3.1 shall be permitted to encroach not more than 6 inches (152 mm) into the required dimensions of the window well.
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R310.2.3.1 Ladder and Steps

Window wells with a vertical depth greater than 44 inches (1118 mm) shall be equipped with a permanently affixed ladder or steps usable with the window in the fully open position. Ladders or steps required by this section shall not be required to comply with Sections R311.7 and R311.8. Ladders or rungs shall have an inside width of not less than 12 inches (305 mm), shall project not less than 3 inches (76 mm) from the wall and shall be spaced not more than 18 inches (457 mm) on center vertically for the full height of the window well.

R310.2.3.2 Drainage

Window wells shall be designed for proper drainage by connecting to the building's foundation drainage system required by Section R405.1 or by an approved alternative method.
Exception: A drainage system for window wells is not required where the foundation is on well-drained soil or sand-gravel mixture soils in accordance with the United Soil Classification System, Group I Soils, as detailed in Table R405.1.

R310.2.4 Emergency Escape and Rescue Openings Under Decks and Porches

Emergency escape and rescue openings shall be permitted to be installed under decks and porches provided that the location of the deck allows the emergency escape and rescue openings to be fully opened and provides a path not less than 36 inches (914 mm) in height to a yard or court.

R310.2.5 Replacement Windows

Replacement windows installed in buildings meeting the scope of this code shall be exempt from the maximum sill height requirements of Sections R310.1 and Sections R310.2.1 and R310.2.2, provided the replacement window meets the following conditions:
  1. The replacement window is the manufacturer's largest standard size window that will fit within the existing frame or existing rough opening. The replacement window is of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.
  2. The replacement window is not part of a change of occupancy.

R310.3 Emergency Escape and Rescue Doors

Where a door is provided as the required emergency escape and rescue opening, it shall be permitted to be a side-hinged door or a slider. Where the opening is below the adjacent grade, it shall be provided with an area well.
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R310.3.1 Minimum Door Opening Size

The minimum net clear height opening for any door that serves as an emergency and escape rescue opening shall be in accordance with Section R310.2.1.

R310.3.2 Area Wells

Area wells shall have a width of not less than 36 inches (914 mm). The area of the area well shall allow the emergency escape and rescue door to be fully opened.
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R310.3.2.1 Ladder and Steps

Area wells with a vertical depth greater than 44 inches (1118 mm) shall be equipped with a permanently affixed ladder or steps usable with the door in the fully open position. Ladders or steps required by this section shall not be required to comply with Sections R311.7 and R311.8. Ladders or rungs shall have an inside width of not less than 12 inches (305 mm), shall project not less than 3 inches (76 mm) from the wall and shall be spaced not more than 18 inches (457 mm) on center vertically for the full height of the exterior stairwell.

R310.3.2.2 Drainage

Area wells shall be designed for proper drainage by connecting to the building's foundation drainage system required by Section R405.1 or by an approved alternative method.
Exception: A drainage system for area wells is not required where the foundation is on well-drained soil or sand-gravel mixture soils in accordance with the United Soil Classification System, Group I Soils, as detailed in Table R405.1.

R310.4 Bars, Grilles, Covers and Screens

Bars, grilles, covers, screens or similar devices are permitted to be placed over emergency escape and rescue openings, bulkhead enclosures, or window wells that serve such openings, provided that the minimum net clear opening size complies with Sections R310.1.1 to R310.2.3, and such devices shall be releasable or removable from the inside without the use of a key, tool, special knowledge or force greater than that required for the normal operation of the escape and rescue opening. The temporary installation or closure of storm shutters, panels, and other approved hurricane protection devices shall be permitted on emergency escape and rescue openings and egress doors during the threat of a storm. Such devices shall not be required to comply with the operational constraints of Section R310.1.1 or R312.2. While such protection is provided, at least one means of escape from the dwelling or dwelling unit shall be provided. The means of escape shall be within the first floor of the dwelling or dwelling unit and shall not be located within a garage without a side-hinged door leading directly to the exterior. Occupants in any part of the dwelling or dwelling unit shall be able to access the means of escape without passing through a lockable door not under their control.

R310.5 Dwelling Additions

Where dwelling additions occur that contain sleeping rooms, an emergency escape and rescue opening shall be provided in each new sleeping room. Where dwelling additions occur that have basements, an emergency escape and rescue opening shall be provided in the new basement.
Exceptions:
  1. An emergency escape and rescue opening is not required in a new basement that contains a sleeping room with an emergency escape and rescue opening.
  2. An emergency escape and rescue opening is not required in a new basement where there is an emergency escape and rescue opening in an existing basement that is accessed from the new basement.

R310.6 Alterations or Repairs of Existing Basements

An emergency escape and rescue opening is not required where existing basements undergo alterations or repairs.
Exception: New sleeping rooms created in an existing basement shall be provided with emergency escape and rescue openings in accordance with Section R310.1.
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Section R311 Means of Egress

R311.1 Means of Egress

Dwellings shall be provided with a means of egress in accordance with this section. The means of egress shall provide a continuous and unobstructed path of vertical and horizontal egress travel from all portions of the dwelling to the required egress door without requiring travel through a garage. The required egress door shall open directly into a public way or to a yard or court that opens to a public way.

R311.2 Egress Door

Not less than one egress door shall be provided for each dwelling unit. The egress door shall be side-hinged, and shall provide a clear width of not less than 32 inches (813 mm) where measured between the face of the door and the stop, with the door open 90 degrees (1.57 rad). The clear height of the door opening shall be not less than 78 inches (1981 mm) in height measured from the top of the threshold to the bottom of the stop. Other doors shall not be required to comply with these minimum dimensions. Egress doors shall be readily openable from inside the dwelling without the use of a key or special knowledge or effort.
Exception: Buildings that are 400 square feet or less and that are intended for use in conjunction with one- and two- family residences are not subject to the door height and width requirements of this code.
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R311.3 Floors and Landings at Exterior Doors

There shall be a landing or floor on each side of each exterior door. The width of each landing shall be not less than the door served. Every landing shall have a dimension of not less than 36 inches (914 mm) measured in the direction of travel. The slope at exterior landings shall not exceed 1/4 unit vertical in 12 units horizontal (2 percent).
Exception: Exterior balconies less than 60 square feet (5.6 m2) and only accessed from a door are permitted to have a landing less than 36 inches (914 mm) measured in the direction of travel.
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R311.3.1 Floor Elevations at the Required Egress Doors

Landings or finished floors at the required egress door shall be not more than 11/2 inches (38 mm) lower than the top of the threshold.
Exception: The landing or floor on the exterior side shall be not more than 73/4 inches (196 mm) below the top of the threshold.
Where exterior landings or floors serving the required egress door are not at grade, they shall be provided with access to grade by means of a ramp in accordance with Section R311.8 or a stairway in accordance with Section R311.7.

R311.3.2 Floor Elevations for Other Exterior Doors

Doors other than the required egress door shall be provided with landings or floors not more than 73/4 inches (196 mm) below the top of the threshold.
Exception: A top landing is not required where a stairway of not more than two risers is located on the exterior side of the door.

R311.3.3 Storm and Screen Doors

Storm and screen doors shall be permitted to swing over exterior stairs and landings.

R311.4 Vertical Egress

Egress from habitable levels including habitable attics and basements not provided with an egress door in accordance with Section R311.2 shall be by a ramp in accordance with Section R311.8 or a stairway in accordance with Section R311.7.

R311.5 Construction

R311.5.1 Attachment

Exterior landings, decks, balconies, stairs and similar facilities shall be positively anchored to the primary structure to resist both vertical and lateral forces or shall be designed to be self-supporting. Attachment shall not be accomplished by use of toenails or nails subject to withdrawal.
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R311.6 Hallways

The width of a hallway shall be not less than 3 feet (914 mm).

R311.7 Stairways

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R311.7.1 Width

Stairways shall be not less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height. The clear width of the stairway at and below the handrail height, including treads and landings, shall be not less than 311/2 inches (787 mm) where a handrail is installed on one side and 27 inches (698 mm) where handrails are provided on both sides.
Exception: The width of spiral stairways shall be in accordance with Section R311.7.10.1.

R311.7.2 Headroom

The headroom in stairways shall be not less than 6 feet 8 inches (2032 mm) measured vertically from the sloped line adjoining the tread nosing or from the floor surface of the landing or platform on that portion of the stairway.
Exceptions:
  1. Where the nosings of treads at the side of a flight extend under the edge of a floor opening through which the stair passes, the floor opening shall be allowed to project horizontally into the required headroom not more than 43/4 inches (121 mm).
  2. The headroom for spiral stairways shall be in accordance with Section R311.7.10.1.
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R311.7.3 Vertical Rise

A flight of stairs shall not have a vertical rise larger than 151 inches (3835 mm) between floor levels or landings.
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R311.7.4 Walkline

The walkline across winder treads shall be concentric to the curved direction of travel through the turn and located 12 inches (305 mm) from the side where the winders are narrower. The 12-inch (305 mm) dimension shall be measured from the widest point of the clear stair width at the walking surface of the winder. If winders are adjacent within the flight, the point of the widest clear stair width of the adjacent winders shall be used.
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R311.7.5 Stair Treads and Risers

Stair treads and risers shall meet the requirements of this section. For the purposes of this section, dimensions and dimensioned surfaces shall be exclusive of carpets, rugs or runners.
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