The provisions of this chapter shall govern the structural design of buildings, structures and portions thereof regulated by this code.
Exception: Buildings and structures located within the high-velocity hurricane zone shall comply with the provisions of Sections 1605, 1607, 1611, 1616 through 1626, and, as applicable in flood hazard areas, Section 1612.
The following terms are defined in Chapter 2:
LIVE LOAD (ROOF).
PANEL (PART OF A STRUCTURE).
|Di||=||Weight of ice in accordance with Chapter 10 of ASCE 7.|
|E||=||Combined effect of horizontal and vertical earthquake induced forces as defined in Section 2.3.6 of ASCE 7.|
|F||=||Load due to fluids with well-defined pressures and maximum heights.|
|Fa||=||Flood load in accordance with Chapter 5 of ASCE 7.|
|H||=||Load due to lateral earth pressures, ground water pressure or pressure of bulk materials.|
|L||=||Roof live load greater than 20 psf (0.96 kN/m2) and floor live load.|
|Lr||=||Roof live load of 20 psf (0.96 kN/m2) or less.|
|T||=||Cumulative effect of self-straining load forces and effects.|
|Vasd||=||Nominal design wind speed (3-second gust), miles per hour (mph) (km/hr) where applicable.|
|Vult||=||Ultimate design wind speed (3-second gust), miles per hour (mph) (km/hr) determined from Figure 1609.3(1), 1609.3(2), 1609.3(3) or 1609.3(4) or ASCE 7.|
|W||=||Load due to wind pressure.|
|Wi||=||Wind-on-ice in accordance with Chapter 10 of ASCE 7.|
The ground snow load, pg, shall be indicated. In areas where the ground snow load, pg, exceeds 10 pounds per square foot (psf) (0.479 kN/m2), the following additional information shall also be provided, regardless of whether snow loads govern the design of the roof:
For buildings located in whole or in part in flood hazard areas as established in Section 1612.3, the documentation pertaining to design, if required in Section 1612.5, shall be included and the following information, referenced to the datum on the community's Flood Insurance Rate Map (FIRM), shall be shown, regardless of whether flood loads govern the design of the building:
The following roof rain load parameters shall be shown regardless of whether the rain loads govern the design:
Buildings and other structures, and parts thereof, shall be designed and constructed to support safely the factored loads in load combinations defined in this code without exceeding the appropriate strength limit states for the materials of construction. Alternatively, buildings and other structures, and parts thereof, shall be designed and constructed to support safely the nominal loads in load combinations defined in this code without exceeding the appropriate specified allowable stresses for the materials of construction.
Structural systems and members thereof shall be designed to have adequate stiffness to limit deflections and lateral drift. See Section 12.12.1 of ASCE 7 for drift limits applicable to earthquake loading.
DEFLECTION LIMITSa, b, c, h, i
|CONSTRUCTION||L||S or W f||D + Ld, g|
|Supporting plaster or stucco ceiling||l/360||l/360||l/240|
|Supporting nonplaster ceiling||l/240||l/240||l/180|
|Not supporting ceiling||l/180||l/180||l/120|
|Members supporting screen surfacej||l/60|
|With plaster or stucco finishes||—||l/360||—|
|With other brittle finishes||—||l/240||—|
|With flexible finishes||—||l/120||—|
|With plaster or stucco finishes||l/360||—||—|
|With other brittle finishes||l/240||—||—|
|With flexible finishes||l/120||—||—|
For SI: 1 foot = 304.8 mm.
Load effects on structural members and their connections shall be determined by methods of structural analysis that take into account equilibrium, general stability, geometric compatibility and both short- and long-term material properties.
Members that tend to accumulate residual deformations under repeated service loads shall have included in their analysis the added eccentricities expected to occur during their service life.
Any system or method of construction to be used shall be based on a rational analysis in accordance with well-established principles of mechanics. Such analysis shall result in a system that provides a complete load path capable of transferring loads from their point of origin to the load-resisting elements.
The total lateral force shall be distributed to the various vertical elements of the lateral force-resisting system in proportion to their rigidities, considering the rigidity of the horizontal bracing system or diaphragm. Rigid elements assumed not to be a part of the lateral force-resisting system are permitted to be incorporated into buildings provided their effect on the action of the system is considered and provided for in the design. A diaphragm is rigid for the purpose of distribution of story shear and torsional moment when the lateral deformation of the diaphragm is less than or equal to two times the average story drift. Where required by ASCE 7, provisions shall be made for the increased forces induced on resisting elements of the structural system resulting from torsion due to eccentricity between the center of application of the lateral forces and the center of rigidity of the lateral force-resisting system.
Every structure shall be designed to resist the overturning effects caused by the lateral forces specified in this chapter. See Section 1609 for wind loads, Section 1610 for lateral soil loads and Section 1613 for earthquake loads.
Each building and structure shall be assigned a risk category in accordance with Table 1604.5. Where a referenced standard specifies an occupancy category, the risk category shall not be taken as lower than the occupancy category specified therein. Where a referenced standard specifies that the assignment of a risk category be in accordance with ASCE 7, Table 1.5-1, Table 1604.5 shall be used in lieu of ASCE 7, Table 1.5-1.
|RISK CATEGORY||NATURE OF OCCUPANCY|
|I||Buildings and other structures that represent a low hazard to human life in the event of failure, including but not limited to:|
|II||Buildings and other structures except those listed in Risk Categories I, III and IV.|
|III||Buildings and other structures that represent a substantial hazard to human life in the event of failure, including but not limited to: |
|IV||Buildings and other structures designated as essential facilities, including but not limited to: |
Where a building or structure is occupied by two or more occupancies not included in the same risk category, it shall be assigned the classification of the highest risk category corresponding to the various occupancies. Where buildings or structures have two or more portions that are structurally separated, each portion shall be separately classified. Where a separated portion of a building or structure provides required access to, required egress from or shares life safety components with another portion having a higher risk category, both portions shall be assigned to the higher risk category.
Exception: Where a storm shelter designed and constructed in accordance with ICC 500 is provided in a building, structure or portion thereof normally occupied for other purposes, the risk category for the normal occupancy of the building shall apply unless the storm shelter is a designated emergency shelter in accordance with Table 1604.5.
Where supported by attachment to an exterior wall, decks shall be positively anchored to the primary structure and designed for both vertical and lateral loads as applicable. Such attachment shall not be accomplished by the use of toenails or nails subject to withdrawal. Where positive connection to the primary building structure cannot be verified during inspection, decks shall be self-supporting. Connections of decks with cantilevered framing members to exterior walls or other framing members shall be designed for both of the following:
Buildings and other structures and portions thereof shall be designed to resist:
Applicable loads shall be considered, including both earthquake and wind, in accordance with the specified load combinations. Each load combination shall also be investigated with one or more of the variable loads set to zero.
Where the load combinations with overstrength factor in Sections 2.3.6 and 2.4.5 of ASCE 7 apply, they shall be used as follows:
Where strength design or load and resistance factor design is used, buildings and other structures, and portions thereof, shall be designed to resist the most critical effects resulting from the following combinations of factored loads:
Where allowable stress design (working stress design), as permitted by this code, is used, structures and portions thereof shall resist the most critical effects resulting from the following combinations of loads:
In lieu of the basic load combinations specified in Section 1605.3.1, structures and portions thereof shall be permitted to be designed for the most critical effects resulting from the following combinations. When using these alternative allowable stress load combinations that include wind or seismic loads, allowable stresses are permitted to be increased or load combinations reduced where permitted by the material chapter of this code or the referenced standards. For load combinations that include the counteracting effects of dead and wind loads, only two-thirds of the minimum dead load likely to be in place during a design wind event shall be used. When using allowable stresses that have been increased or load combinations that have been reduced as permitted by the material chapter of this code or the referenced standards, where wind loads are calculated in accordance with Chapters 26 through 31 of ASCE 7, the coefficient (ω) in the following equations shall be taken as 1.3. For other wind loads, (ω) shall be taken as 1. When allowable stresses have not been increased or load combinations have not been reduced as permitted by the material chapter of this code or the referenced standards, (ω) shall be taken as 1. When using these alternative load combinations to evaluate sliding, overturning and soil bearing at the soil-structure interface, the reduction of foundation overturning from Section 12.13.4 in ASCE 7 shall not be used. When using these alternative basic load combinations for proportioning foundations for loadings, which include seismic loads, the vertical seismic load effect, Ev, in Equation 12.4-4 of ASCE 7 is permitted to be taken equal to zero.
|OCCUPANCY OR USE||UNIFORM |
|1. Apartments (see residential)||—||—|
|2. Access floor systems|
|3. Armories and drill rooms||150n||—|
|4. Assembly areas||—|
|Fixed seats (fastened to floor)||60m|
|Follow spot, projections and |
|Other assembly areas||100m|
|5. Balconies and decksh||1.5 times the |
live load for thearea served. Not
required toexceed 100
|First floor |
|Same as |
|9. Dining rooms and restaurants||100m||—|
|10. Dwellings (see residential)||—||—|
|11. Elevator machine room and control |
room grating(on area of 2 inches by 2 inches)
|12. Finish light floor plate construction |
(on area of 1 inch by 1 inch)
|13. Fire escapes||100||—|
|On single-family dwellings only||40|
|14. Garages (passenger vehicles only) |
Trucks and buses
|See Section 1607.7|
|15. Handrails, guards and grab bars||See Section 1607.8|
|16. Helipads||See Section 1607.6|
|Corridors above first floor||80||1,000|
|Operating rooms, laboratories||60||1,000|
|18. Hotels (see residential)||—||—|
|Corridors above first floor||80||1,000|
|Stack rooms||150b, n||1,000|
|21. Marquees, except one- and two-family||75||—|
|22. Office buildings|
|Corridors above first floor||80||2,000|
|File and computer rooms shall be |
designed for heavier loads basedon anticipated occupancy
|Lobbies and first-floor corridors||100||2,000|
|23. Penal institutions||—|
|24. Recreational uses:||—|
|Bowling alleys, poolrooms and |
|Dance halls and ballrooms||100m|
|Ice skating rink||250n|
|Reviewing stands, grandstands and||100c, m|
|Roller skating rink||100m|
|Stadiums and arenas with fixed |
seats (fastened to floor)
|One- and two-family dwellings|
|Uninhabitable attics without |
|Uninhabitable attics with storagei, j, k||20|
|Habitable attics and sleeping areask||30|
|Canopies, including marquees||20|
|All other areas||40|
|Hotels and multifamily dwellings|
|Private rooms and corridors serving |
|Public roomsm and corridors serving |
|All roof surfaces subject to maintenance |
|Awnings and canopies:|
|Fabric construction supported by a |
|All other construction, except one- |
and two-family dwellings
|Ordinary flat, pitched, and curved |
roofs (that are not occupiable)
|Primary roof members exposed to a |
|Single panel point of lower chord of |
roof trusses or any point alongprimary structural members
supporting roofs over manufacturing,storage warehouses, and
|All other primary roof members||300|
|All other similar areas||Note 1||Note 1|
|Corridors above first floor||80||1,000|
|28. Scuttles, skylight ribs and accessible |
|29. Sidewalks, vehicular driveways and |
yards, subject to trucking
|30. Stairs and exits|
|One- and two-family dwellings||40||300f|
|31. Storage warehouses (shall be designed |
for heavier loads if required foranticipated storage)
|Wholesale, all floors||125n||1,000|
|33. Vehicle barriers||See Section 1607.8.3|
|34. Walkways and elevated platforms |
(other than exitways)
|35. Yards and terraces, pedestrians||100m||—|
For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm2, 1 square foot = 0.0929 m2, 1 pound per square foot = 0.0479 kN/m2, 1 pound = 0.004448 kN, 1 pound per cubic foot = 16 kg/m3.
Landing areas designed for a design basis helicopter with maximum take-off weight of 3,000-pounds (13.35 kN) shall be identified with a 3,000 pound (13.34 kN) weight limitation. The landing area weight limitation shall be indicated by the numeral "3" (kips) located in the bottom right corner of the landing area as viewed from the primary approach path. The indication for the landing area weight limitation shall be a minimum 5 feet (1524 mm) in height.
Where a structure or portions of a structure are accessed and loaded by fire department access vehicles and other similar emergency vehicles, the structure shall be designed for the greater of the following loads:
Garages designed to accommodate vehicles that exceed a 10,000-pound (4536 kg) gross vehicle weight rating, shall be designed using the live loading specified by Section 1607.7.1. For garages the design for impact and fatigue is not required.
Exception: The vehicular live loads and load placement are allowed to be determined using the actual vehicle weights for the vehicles allowed onto the garage floors, provided such loads and placement are based on rational engineering principles and are approved by the building official, but shall not be less than 50 psf (2.9 kN/m2). This live load shall not be reduced.
Subject to the limitations of Sections 1607.10.1.1 through 1607.10.1.3 and Table 1607.1, members for which a value of KLLAT is 400 square feet (37.16 m2) or more are permitted to be designed for a reduced uniformly distributed live load, L, in accordance with the following equation:
L = Reduced design live load per square foot (m2) of area supported by the member.
AT = Tributary area, in square feet (m2).
L shall be not less than 0.50Lo for members supporting one floor and L shall be not less than 0.40Lo for members supporting two or more floors.
LIVE LOAD ELEMENT FACTOR, KLL
|Exterior columns without cantilever slabs||4|
|Edge columns with cantilever slabs||3|
|Corner columns with cantilever slabs||2|
|Edge beams without cantilever slabs||2|
|All other members not identified above including:||1|
|Edge beams with cantilever slabs|
|Members without provisions for continuous shear |
transfer normal to their span
Live loads that exceed 100 psf (4.79 kN/m2) shall not be reduced.
As an alternative to Section 1607.10.1 and subject to the limitations of Table 1607.1, uniformly distributed live loads are permitted to be reduced in accordance with the following provisions. Such reductions shall apply to slab systems, beams, girders, columns, piers, walls and foundations.
- (Equation 16-24)(Equation 16-25)
Ordinary flat, pitched and curved roofs, and awnings and canopies other than of fabric construction supported by a skeleton structure, are permitted to be designed for a reduced uniformly distributed roof live load, Lr, as specified in the following equations or other controlling combinations of loads as specified in Section 1605, whichever produces the greater load effect.
In structures such as greenhouses, where special scaffolding is used as a work surface for workers and materials during maintenance and repair operations, a lower roof load than specified in the following equations shall not be used unless approved by the building official. Such structures shall be designed for a minimum roof live load of 12 psf (0.58 kN/m2).
where: 12 ≤ Lr ≤ 20
For SI: Lr = LoR1R2
The reduction factors R1 and R2 shall be determined as follows:
For SI: 1.2 - 0.011At for 18.58 square meters < At < 55.74 square meters
At = Tributary area (span length multiplied by effective width) in square feet (m2) supported by the member, and
F = For a sloped roof, the number of inches of rise per foot (for SI: F = 0.12 × slope, with slope expressed as a percentage), or for an arch or dome, the rise-to-span ratio multiplied by 32.
Roof structures that support photovoltaic panel systems shall be designed to resist each of the following conditions:
Solar photovoltaic panels or modules that are independent structures and do not have accessible/occupied space underneath are not required to accommodate a roof photovoltaic live load, provided the area under the structure is restricted to keep the public away. All other loads and combinations in accordance with Section 1605 shall be accommodated.
Solar photovoltaic panels or modules that are designed to be the roof, span to structural supports and have accessible/occupied space underneath shall have the panels or modules and all supporting structures designed to support a roof photovoltaic live load, as defined in Section 1607.12.5.1 in combination with other applicable loads. Solar photovoltaic panels or modules in this application are not permitted to be classified as "not accessible" in accordance with Section 1607.12.5.1.
The maximum wheel loads of the crane shall be increased by the percentages shown below to determine the induced vertical impact or vibration force:
|Monorail cranes (powered)||25 percent|
|Cab-operated or remotely operated bridge cranes (powered)||25 percent|
|Pendant-operated bridge cranes (powered)||10 percent|
|Bridge cranes or monorail cranes with hand-geared bridge, trolley and hoist||0 percent|
The ground snow loads to be used in determining the design snow loads for roofs shall be determined in accordance with ASCE 7 or Figure 1608.2 for the contiguous United States and Table 1608.2 for Alaska. Site-specific case studies shall be made in areas designated "CS" in Figure 1608.2. Ground snow loads for sites at elevations above the limits indicated in Figure 1608.2 and for all sites within the CS areas shall be approved. Ground snow load determination for such sites shall be based on an extreme value statistical analysis of data available in the vicinity of the site using a value with a 2-percent annual probability of being exceeded (50-year mean recurrence interval). Snow loads are zero for Hawaii, except in mountainous regions as approved by the building official.
GROUND SNOW LOADS, pg, FOR ALASKAN LOCATIONS
|LOCATION||POUNDS PER |
|LOCATION||POUNDS PER |
|LOCATION||POUNDS PER |
|Anchorage||50||Gulkana||70||St. Paul Islands||40|
For SI: 1 pound per square foot = 0.0479 kN/m2.
Wind loads on every building or structure shall be determined in accordance with Chapters 26 to 30 of ASCE 7. Wind shall be assumed to come from any horizontal direction and wind pressures shall be assumed to act normal to the surface considered.
The wind speeds in Figures 1609.3(1), 1609.3(2), 1609.3(3) and 1609.3(4) are ultimate design wind speeds, Vult, and shall be converted in accordance with Section 1609.3.1 to nominal design wind speeds, Vasd, when the provisions of the standards referenced in Exceptions 4 and 5 are used.
The provisions of ICC 600 are applicable only to buildings located within Exposure B or C as defined in Section 1609.4. The provisions of ICC 600, AWC WFCM and AISI S230 shall not apply to buildings sited on the upper half of an isolated hill, ridge or escarpment meeting the following conditions:
In wind-borne debris regions, glazed openings in buildings shall be impact resistant or protected with an impact-resistant covering meeting the requirements of ANSI/DASMA 115 (for garage doors and rolling doors) or TAS 201, 202 and 203, AAMA 506, ASTM E1996 and ASTM E1886 referenced herein, or an approved impact-resistant standard as follows:
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 strength design wind speed, Vult, as follows:
18.104.22.168 Wind Zone 1—130 mph ≤ ultimate design wind speed, Vult < 140 mph.
22.214.171.124 Wind Zone 2—140 mph ≤ ultimate design wind speed, Vult < 150 mph at greater than one mile (1.6 km) from the coastline. The coastline shall be measured from the mean high water mark.
126.96.36.199 Wind Zone 3—150 mph (58 m/s) ≤ ultimate design wind speed, Vult ≤ 170 mph (63 m/s), or 140 mph (54 m/s) ≤ ultimate design wind speed, Vult ≤ 170 mph (63 m/s) and within one mile (1.6 km) of the coastline. The coastline shall be measured from the mean high water mark.
188.8.131.52 Wind Zone 4— ultimate design wind speed, Vult >170 mph (63 m/s).
The ultimate design wind speed, Vult, in mph, for the determination of the wind loads shall be determined by Figures 1609.3(1), 1609.3(2), 1609.3(3) and 1609.3(4). The ultimate design wind speed, Vult, for use in the design of Risk Category II buildings and structures shall be obtained from Figure 1609.3(1). The ultimate design wind speed, Vult, for use in the design of Risk Category III buildings and structures shall be obtained from Figure 1609.3(2). The ultimate design wind speed, Vult, for use in the design of Risk Category IV buildings and structures shall be obtained from Figure 1609.3(3). The ultimate design wind speed, Vult, for use in the design of Risk Category I buildings and structures shall be obtained from Figure 1609.3(4). The ultimate design wind speed, Vult, for the special wind regions indicated near mountainous terrain and near gorges shall be in accordance with local jurisdiction requirements. The ultimate design wind speeds, Vult, determined by the local jurisdiction shall be in accordance with Chapter 26 of ASCE 7. The exact location of wind speed lines shall be established by local ordinance using recognized physical landmarks such as major roads, canals, rivers and lake shores wherever possible.
Where required, the ultimate design wind speeds of Figures 1609.3(1), 1609.3(2), 1609.3(3) and 1609.3(4) shall be converted to nominal design wind speeds, Vasd, using Table 1609.3.1 or Equation 16-33.
WIND SPEED CONVERSIONSa, b, c
For SI: 1 mile per hour = 0.44 m/s.
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 1609.4.3 from the categories defined below, for the purpose of assigning an exposure category as defined in Section 1609.4.3.
- 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.
- Flat, unobstructed areas and water surfaces. This category includes smooth mud flats, salt flats and unbroken ice.
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 Exposure B or D does 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.
b = Exposed width, feet (mm) of the roof tile.
GCp = Roof pressure coefficient for each applicable roof zone determined from Chapter 30 of ASCE 7. Roof coefficients shall not be adjusted for internal pressure.
L = Length, feet (mm) of the roof tile.
La = Moment arm, feet (mm) from the axis of rotation to the point of uplift on the roof tile. The point of uplift shall be taken at 0.76L from the head of the tile and the middle of the exposed width. For roof tiles with nails or screws (with or without a tail clip), the axis of rotation shall be taken as the head of the tile for direct deck application or as the top edge of the batten for battened applications. For roof tiles fastened only by a nail or screw along the side of the tile, the axis of rotation shall be determined by testing. For roof tiles installed with battens and fastened only by a clip near the tail of the tile, the moment arm shall be determined about the top edge of the batten with consideration given for the point of rotation of the tiles based on straight bond or broken bond and the tile profile.
Ma = Aerodynamic uplift moment, feet-pounds (N-mm) acting to raise the tail of the tile.
qh = Wind velocity pressure, psf (kN/m2) determined from Section 26.10.2 of ASCE 7.
Concrete and clay roof tiles complying with the following limitations shall be designed to withstand the aerodynamic uplift moment as determined by this section.
Pressures from Table 1609.6(1) for wind loading actions on garage doors and rolling doors for buildings designed as enclosed shall be permitted.
|ULTIMATE DESIGN WIND SPEED (Vult) DETERMINED IN ACCORDANCE WITH SECTION 1609.3 (MPH - 3 SECOND GUST)|
|100 MPH||110 MPH||120 MPH||130 MPH||140 MPH||150 MPH||160 MPH||170 MPH||180 MPH||190 MPH||200 MPH|
|Roof Angle 0 — 10 degrees|
|8||8||+ 10.0||— 10.0||+ 10.5||— 11.9||+ 12.5||— 14.2||+ 14.7||— 16.6||+ 17.1||— 19.3||+ 19.6||— 22.2||+ 22.3||— 25.2||+ 25.1||— 28.5||+ 28.2||— 31.9||+ 31.4||— 35.5||+ 34.8||— 39.4|
|10||10||+ 10.0||— 10.0||+ 10.2||— 11.4||+ 12.1||— 13.6||+ 14.2||— 16.0||+ 16.5||— 18.5||+ 18.9||— 21.2||+ 21.5||— 24.2||+ 24.3||— 27.3||+ 27.3||— 30.6||+ 30.4||— 34.1||+ 33.7||— 37.8|
|14||14||+ 10.0||— 10.0||+ 10.0||— 10.8||+ 11.5||— 12.8||+ 13.5||— 15.0||+ 15.7||— 17.4||+ 18.0||— 20.0||+ 20.5||— 22.8||+ 23.1||— 25.7||+ 25.9||— 28.8||+ 28.9||— 32.1||+ 32.0||— 35.6|
|Roof Angle > 10 degrees|
|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|
ADJUSTMENT FACTOR FOR BUILDING HEIGHT AND EXPOSURE, (λ)
|MEAN ROOF HEIGHT (feet)||EXPOSURE|
Foundation walls and retaining walls shall be designed to resist lateral soil loads. Soil loads specified in Table 1610.1 shall be used as the minimum design lateral soil loads unless determined otherwise by a geotechnical investigation in accordance with Section 1803. Foundation walls and other walls in which horizontal movement is restricted at the top shall be designed for at-rest pressure. Retaining walls free to move and rotate at the top shall be permitted to be designed for active pressure. Design lateral pressure from surcharge loads shall be added to the lateral earth pressure load. Design lateral pressure shall be increased if soils at the site are expansive. Foundation walls shall be designed to support the weight of the full hydrostatic pressure of undrained backfill unless a drainage system is installed in accordance with Sections 1805.4.2 and 1805.4.3.
LATERAL SOIL LOAD
|DESCRIPTION OF BACKFILL MATERIALc||UNIFIED SOIL |
|DESIGN LATERAL SOIL LOADa |
(pound per square foot per foot of depth)
|Active pressure||At-rest pressure|
|Well-graded, clean gravels; gravel-sand mixes||GW||30||60|
|Poorly graded clean gravels; gravel-sand mixes||GP||30||60|
|Silty gravels, poorly graded gravel-sand mixes||GM||40||60|
|Clayey gravels, poorly graded gravel-and-clay mixes||GC||45||60|
|Well-graded, clean sands; gravelly sand mixes||SW||30||60|
|Poorly graded clean sands; sand-gravel mixes||SP||30||60|
|Silty sands, poorly graded sand-silt mixes||SM||45||60|
|Sand-silt clay mix with plastic fines||SM-SC||45||100|
|Clayey sands, poorly graded sand-clay mixes||SC||60||100|
|Inorganic silts and clayey silts||ML||45||100|
|Mixture of inorganic silt and clay||ML-CL||60||100|
|Inorganic clays of low to medium plasticity||CL||60||100|
|Organic silts and silt clays, low plasticity||OL||Note b||Note b|
|Inorganic clayey silts, elastic silts||MH||Note b||Note b|
|Inorganic clays of high plasticity||CH||Note b||Note b|
|Organic clays and silty clays||OH||Note b||Note b|
For SI: 1 pound per square foot per foot of depth = 0.157 kPa/m, 1 foot = 304.8 mm.
Each portion of a roof shall be designed to sustain the load of rainwater that will accumulate on it if the primary drainage system for that portion is blocked plus the uniform load caused by water that rises above the inlet of the secondary drainage system at its design flow. The design rainfall shall be based on the 100-year hourly rainfall rate indicated in Figure 1611.1 or on other rainfall rates determined from approved local weather data.
For SI: R = 0.0098(ds + dh)
dh = Additional depth of water on the undeflected roof above the inlet of secondary drainage system at its design flow (i.e., the hydraulic head), in inches (mm).
ds = Depth of water on the undeflected roof up to the inlet of secondary drainage system when the primary drainage system is blocked (i.e., the static head), in inches (mm).
R = Rain load on the undeflected roof, in psf (kN/m2). When the phrase "undeflected roof" is used, deflections from loads (including dead loads) shall not be considered when determining the amount of rain on the roof.
Within flood hazard areas as established in Section 1612.3, all new construction of buildings, structures and portions of buildings and structures, including substantial improvement and restoration of substantial damage to buildings and structures, shall be designed and constructed to resist the effects of flood hazards and flood loads. For buildings that are located in more than one flood hazard area, the provisions associated with the most restrictive flood hazard area shall apply.
CROSS REFERENCES DEFINING FLOOD-RESISTANT PROVISIONS OF THE FLORIDA BUILDING CODE
|Florida Building Code — Building|
|Chapter 1||Administration||Chapter 14||Exterior Walls|
|107||Construction Documents||Chapter 16||Structural Design|
|111||Certificates of Occupancy and Completion||1603||Construction Documents|
|117||Variances in Flood Hazard Areas||1605||Load Combinations|
|202||Definitions||Chapter 18||Soils and Foundations|
|1804||Excavation, Grading and Fill|
|Chapter 4||Special Detailed Requirements Based on Use and Occupancy||1805||Dampproofing and Waterproofing|
|450||Nursing Homes||Chapter 27||Electrical|
|453||Educational Facilities||2702||Emergency and Standby Power Systems|
|454||Swimming Pools and Bathing Places (Public And Private)|
|Chapter 30||Elevators and Conveying Systems|
|Chapter 8||Interior Finishes||3001||General|
|Chapter 31||Special Construction|
|Chapter 12||Interior Environment||3102||Membrane Structures|
|1203||Ventilation||3109||Coastal Construction Control Line|
|Florida Building Code — Residential|
|Chapter 2||Definitions||Chapter 20||Boilers and Water Heaters|
|Chapter 3||Building Planning||Chapter 22||Special Piping and Storage Systems|
|R301||Design Criteria||M2201||Oil Tanks|
|R309||Garages and Carports|
|R322||Flood-Resistant Construction||Chapter 24||Fuel Gas|
|R401||General||Chapter 26||General Plumbing Requirements|
|R404||Foundation and Retaining Walls||P2601||General|
|Chapter 27||Plumbing Fixtures|
|Chapter 13||General Mechanical System Requirements||P2705||Installation|
|Chapter 30||Sanitary Drainage|
|Chapter 14||Heating and Cooling Equipment||P3001||General|
|Chapter 16||Duct Systems||P3101||Vent Systems|
|Chapter 17||Combustion Air||Chapter 45||Private Swimming Pools|
|Florida Building Code — Existing Building|
|Chapter 2||Definitions||Chapter 7||Alterations — Level I|
|Chapter 3||Compliance Methods||Chapter 11||Additions|
|Chapter 4||Repairs||Chapter 12||Historic Buildings|
|Chapter 13||Relocated or Moved Buildings|
|Chapter 5||Prescriptive Compliance Method||1302||Requirements|
|503||Alterations||Chapter 14||Performance Compliance Methods|
|Florida Building Code — Mechanical|
|Chapter 3||General Regulations||Chapter 6||Duct Systems|
|M603||Duct Construction and Installation|
|M401||General||Chapter 12||Hydronic Piping|
|Chapter 5||Exhaust Systems|
|M501||General||Chapter 13||Fuel Oil Piping and Storage|
|M1305||Fuel Oil System Installation|
|Florida Building Code — Plumbing|
|Chapter 3||General Regulations|
|P309||Flood Hazard Resistance|
|Florida Building Code — Fuel Gas|
|Chapter 3||General Regulations|
The following terms are defined in Chapter 2:
FLOOD INSURANCE RATE MAP (FIRM).
Table 6-1 and Section 6.2.1 in ASCE 24 shall be modified as follows:
Modify Section 9.6 in ASCE 24 by adding an exception as follows:
9.6 Pools. In-ground and above-ground pools shall be designed to withstand all flood-related loads and load combinations. Mechanical equipment for pools such as pumps, heating systems and filtering systems, and their associated electrical systems, shall comply with Chapter 7.
Exception: Equipment for pools, spas and water features shall be permitted below the elevation required in Table 7-1, provided it is elevated to the extent practical, is anchored to prevent flotation and resist flood forces, and is supplied by branch circuits that have ground-fault circuit-interrupter protection.
Every structure, and portion thereof, including nonstructural components that are permanently attached to structures and their supports and attachments, shall be designed and constructed to resist the effects of earthquake motions in accordance with ASCE 7, excluding Chapter 14 and Appendix 11A. The seismic design category for a structure is permitted to be determined in accordance with Section 1613 or ASCE 7.
The parameters SS and S1 shall be determined from the 0.2 and 1-second spectral response accelerations shown on Figures 1613.3.1(1) through 1613.3.1(8). Where S1 is less than or equal to 0.04 and SS is less than or equal to 0.15, the structure is permitted to be assigned Seismic Design Category A.
Where the soil properties are not known in sufficient detail to determine the site class, Site Class D shall be used unless the building official or geotechnical data determines Site Class E or F soils are present at the site.
1613.3.3 Site Coefficients and Adjusted Maximum Considered Earthquake Spectral Response Acceleration Parameters
The maximum considered earthquake spectral response acceleration for short periods, SMS, and at 1-second period, SM1, adjusted for site class effects shall be determined by Equations 16-37 and 16-38, respectively:
VALUES OF SITE COEFFICIENT Fa a
|SITE CLASS||MAPPED SPECTRAL RESPONSE ACCELERATION AT SHORT PERIOD|
|Ss ≤ 0.25||Ss = 0.50||Ss = 0.75||Ss = 1.00||Ss ≥ 1.25|
|F||Note b||Note b||Note b||Note b||Note b|
VALUES OF SITE COEFFICIENT FV a
|SITE CLASS||MAPPED SPECTRAL RESPONSE ACCELERATION AT 1-SECOND PERIOD|
|S1 ≤ 0.1||S1 = 0.2||S1 = 0.3||S1 = 0.4||S1 ≥ 0.5|
|F||Note b||Note b||Note b||Note b||Note b|
Five-percent damped design spectral response acceleration at short periods, SDS, and at 1-second period, SD1, shall be determined from Equations 16-39 and 16-40, respectively:
Structures classified as Risk Category I, II or III that are located where the mapped spectral response acceleration parameter at 1-second period, S1, is greater than or equal to 0.75 shall be assigned to Seismic Design Category E. Structures classified as Risk Category IV that are located where the mapped spectral response acceleration parameter at 1-second period, S1, is greater than or equal to 0.75 shall be assigned to Seismic Design Category F. All other structures shall be assigned to a seismic design category based on their risk category and the design spectral response acceleration parameters, SDS and SD1, determined in accordance with Section 1613.3.4 or the site-specific procedures of ASCE 7. Each building and structure shall be assigned to the more severe seismic design category in accordance with Table 1613.3.5(1) or 1613.3.5(2), irrespective of the fundamental period of vibration of the structure, T.
SEISMIC DESIGN CATEGORY BASED ON SHORT-PERIOD (0.2 second) RESPONSE ACCELERATION
|VALUE OF SDS||RISK CATEGORY|
|I or II||III||IV|
|SDS < 0.167g||A||A||A|
|0.167g ≤ SDS < 0.33g||B||B||C|
|0.33g ≤ SDS < 0.50g||C||C||D|
|0.50g ≤ SDS||D||D||D|
Add the following exception to the end of Section 184.108.40.206 of ASCE 7:
Exception: For isolated structures designed in accordance with this standard, the structural system limitations including structural height limits, in Table 12.2-1 for ordinary steel concentrically braced frames (OCBFs) as defined in Chapter 11 and ordinary moment frames (OMFs) as defined in Chapter 11 are permitted to be taken as 160 feet (48 768 mm) for structures assigned to Seismic Design Category D, E or F, provided that the following conditions are satisfied:
Modify ASCE 7 Section 220.127.116.11.1 as follows:
18.104.22.168.1 Transfer of anchorage forces into diaphragm. Diaphragms shall be provided with continuous ties or struts between diaphragm chords to distribute these anchorage forces into the diaphragms. Diaphragm connections shall be positive, mechanical or welded. Added chords are permitted to be used to form subdiaphragms to transmit the anchorage forces to the main continuous cross-ties. The maximum length-to-width ratio of a wood, wood structural panel or untopped steel deck sheathed structural subdiaphragm that serves as part of the continuous tie system shall be 2.5 to 1. Connections and anchorages capable of resisting the prescribed forces shall be provided between the diaphragm and the attached components. Connections shall extend into the diaphragm a sufficient distance to develop the force transferred into the diaphragm.
Frame structures constructed primarily of reinforced or prestressed concrete, either cast-in-place or precast, or a combination of these, shall conform to the requirements of Section 4.10 of ACI 318. Where ACI 318 requires that nonprestressed reinforcing or prestressing steel pass through the region bounded by the longitudinal column reinforcement, that reinforcing or prestressing steel shall have a minimum nominal tensile strength equal to two-thirds of the required one-way vertical strength of the connection of the floor or roof system to the column in each direction of beam or slab reinforcement passing through the column.
Exception: Where concrete slabs with continuous reinforcement having an area not less than 0.0015 times the concrete area in each of two orthogonal directions are present and are either monolithic with or equivalently bonded to beams, girders or columns, the longitudinal reinforcing or prestressing steel passing through the column reinforcement shall have a nominal tensile strength of one-third of the required one-way vertical strength of the connection of the floor or roof system to the column in each direction of beam or slab reinforcement passing through the column.
1615.3.2 Structural Steel, Open Web Steel Joist or Joist Girder, or Composite Steel and Concrete Frame Structures
End connections of all beams and girders shall have a minimum nominal axial tensile strength equal to the required vertical shear strength for allowable stress design (ASD) or two-thirds of the required shear strength for load and resistance factor design (LRFD) but not less than 10 kips (45 kN). For the purpose of this section, the shear force and the axial tensile force need not be considered to act simultaneously.
Exception: Where beams, girders, open web joist and joist girders support a concrete slab or concrete slab on metal deck that is attached to the beam or girder with not less than 3/8-inch-diameter (9.5 mm) headed shear studs, at a spacing of not more than 12 inches (305 mm) on center, averaged over the length of the member, or other attachment having equivalent shear strength, and the slab contains continuous distributed reinforcement in each of two orthogonal directions with an area not less than 0.0015 times the concrete area, the nominal axial tension strength of the end connection shall be permitted to be taken as half the required vertical shear strength for ASD or one-third of the required shear strength for LRFD, but not less than 10 kips (45 kN).
Longitudinal ties shall consist of continuous reinforcement in slabs; continuous or spliced decks or sheathing; continuous or spliced members framing to, within or across walls; or connections of continuous framing members to walls. Longitudinal ties shall extend across interior load-bearing walls and shall connect to exterior load-bearing walls and shall be spaced at not greater than 10 feet (3038 mm) on center. Ties shall have a minimum nominal tensile strength, TT, given by Equation 16-41. For ASD the minimum nominal tensile strength shall be permitted to be taken as 1.5 times the allowable tensile stress times the area of the tie.
L = The span of the horizontal element in the direction of the tie, between bearing walls, feet (m).
w = The weight per unit area of the floor or roof in the span being tied to or across the wall, psf (N/m2).
S = The spacing between ties, feet (m).
αT = A coefficient with a value of 1,500 pounds per foot (2.25 kN/m) for masonry bearing wall structures and a value of 375 pounds per foot (0.6 kN/m) for structures with bearing walls of cold-formed steel light-frame construction.
Perimeter ties shall consist of continuous reinforcement in slabs; continuous or spliced decks or sheathing; continuous or spliced members framing to, within or across walls; or connections of continuous framing members to walls. Ties around the perimeter of each floor and roof shall be located within 4 feet (1219 mm) of the edge and shall provide a nominal strength in tension not less than Tp, given by Equation 16-42. For ASD the minimum nominal tensile strength shall be permitted to be taken as 1.5 times the allowable tensile stress times the area of the tie.
The deflection of any structural member or component when subjected to live, wind and other superimposed loads set forth herein shall not exceed the following:
|1.||Roof and ceiling or components supporting plaster||L/360|
|2.||Roof members or components not supporting plaster under||L/240|
|3.||Structural metal roof panels of cold-formed steel construction||L/180|
|4.||Floor members or components||L/360|
|5.||Vertical members and wall members or components consisting of or supporting material that hardens in place, is brittle or lacks resistance to cracking caused by bending strains||L/360|
|6.||Vertical members and wall members or components not required to meet the conditions of Section 1616.3, Item 5||L/180|
|7.||Roof and vertical members, wall members and panels of carports, canopies, marquees, the roof projection is greater than 12 feet (3.7 m) in the direction of the span, for free-standing roofs and roofs supported by existing structures. Existing structures supporting such roofs shall be capable of supporting the additional loading||L/180|
|8.||For Group R3 occupancies only, roof and vertical members, wall members and panels of carports, canopies, marquees, patio covers, utility sheds and similar minor structures not to be considered living areas, where the roof projection is 12 feet (3.7 m) or less in the direction of the span and for free-standing roofs and roofs supported by existing structures||L/80|
|9.||Members supporting screens only||L/80|
|10.||Storm shutters and fold-down awnings, which in the closed position shall provide a minimum clear separation from the glass of 1 inch (25 mm) but not to exceed 2 inches (51 mm) when the shutter or awning is at its maximum point of permissible deflection||L/30|
|11.||Roofs and exterior walls of utility sheds having maximum dimensions of 10 feet (3 m) length, 10 feet (3 m) width, and 7 feet (2.1 m) height||L/80|
|12.||Roofs and exterior walls of storage buildings larger than utility sheds||L/180|
Buildings and structures, and every portion thereof, shall be designed and constructed to meet the requirements of Chapters 26 through 31 of ASCE 7.
Exception: Exposed mechanical equipment or appliances fastened to a roof or installed on the ground in compliance with the code using rated stands, platforms, curbs, slabs, walls, or other means are deemed to comply with the wind resistance requirements of the 2007 Florida Building Code, as amended. Further support or enclosure of such mechanical equipment or appliances is not required by a state or local official having authority to enforce the Florida Building Code.
Wind velocity (3-second gust) used in structural calculations shall be as follows:
- Risk Category I Buildings and Structures: 165 mph
- Risk Category II Buildings and Structures: 175 mph
- Risk Category III Buildings and Structures: 186 mph
- Risk Category IV Buildings and Structures: 195 mph
Exception: Exposed mechanical equipment or appliances fastened to a roof or installed on the ground in compliance with the code using rated stands, platforms, curbs, slabs, walls, or other means are deemed to comply with the wind-resistance requirements of the 2007 Florida Building Code, as amended. Further support or enclosure of such mechanical equipment or appliances is not required by a state or local official having authority to enforce the Florida Building Code.
Exception: Screen enclosures shall be permitted to be designed in accordance with the AAF Guide to Aluminum Construction in High Wind Areas. Construction documents based on the AAF Guide to Aluminum Construction in High Wind Areas shall be prepared and signed and sealed by a Florida registered architect or engineer.
Where cladding assemblies (including cladding and connections) or roofing framing assemblies (including portions of roof structure and connections) are such that their load-carrying capacity or deformation under load cannot be calculated by rational analysis, the assemblies may be tested to resist the fatigue loading sequence given by Table 1625.4.
Assemblies shall be tested with no resultant failure or distress and shall have a recovery of at least 90 percent over maximum deflection.
Any cladding assembly not incorporated into the Florida Building Code, Building after successfully completing the impact test outlined in Section 1626, shall be subject to fatigue loading testing and shall obtain product approval by the building official.
FATIGUE LOADING SEQUENCE
|RANGE OF TEST||NUMBER OF CYCLES1|
|0 to 0.5pmax2||600|
|0 to 0.6pmax||70|
|0 to 1.3pmax||1|
CYCLIC WIND PRESSURE LOADING
|INWARD ACTING PRESSURE||OUTWARD ACTING PRESSURE|
|RANGE||NUMBER OF CYCLES1||RANGE||NUMBER OF CYCLES1|
|0.2 PMAX to 0.5 PMAX2||3,500||0.3 PMAX to 1.0 PMAX||50|
|0.0 PMAX to 0.6 PMAX||300||0.5 PMAX to 0.8 PMAX||1,050|
|0.5 PMAX to 0.8 PMAX||600||0.0 PMAX to 0.6 PMAX||50|
|0.3 PMAX to 1.0 PMAX||100||0.2 PMAX to 0.5 PMAX||3,350|
All parts or systems of a building or structure envelope such as, but not limited, to exterior walls, roof, outside doors, skylights, glazing and glass block shall meet impact test criteria or be protected with an external protection device that meets the impact test criteria. Test procedures to determine resistance to wind-borne debris of wall cladding, outside doors, skylights, glazing, glass block, shutters and any other external protection devices shall be performed in accordance with this section.
Exception: The following structures or portion of structures shall not be required to meet the provisions of this section:
All connectors shall be specified by the building designer of record for all loads except impact.