Part I ‒ Administration

Chapter 1 Administration

Part II ‒ Definitions

Chapter 2 Definitions

Part III ‒ Building Planning and Construction

Chapter 3 Building Planning

Chapter 4 Foundations

Chapter 5 Floors

Chapter 6 Wall Construction

Chapter 7 Wall Covering

Chapter 8 Roof-Ceiling Construction

Chapter 9 Roof Assemblies

Chapter 10 Chimneys and Fireplaces

Part IV ‒ Energy Conservation

Chapter 11 Energy Efficiency

Part V ‒ Mechanical

Chapter 12 Mechanical Administration

Chapter 13 General Mechanical System Requirements

Chapter 14 Heating and Cooling Equipment

Chapter 15 Exhaust Systems

Chapter 16 Duct Systems

Chapter 17 Combustion Air

Chapter 18 Chimneys and Vents

Chapter 19 Special Fuel-Burning Equipment

Chapter 20 Boilers and Water Heaters

Chapter 21 Hydronic Piping

Chapter 22 Special Piping and Storage Systems

Chapter 23 Solar Systems

Part VI ‒ Fuel Gas

Chapter 24 Fuel Gas

Part VII ‒ Plumbing

Chapter 25 Plumbing Administration

Chapter 26 General Plumbing Requirements

Chapter 27 Plumbing Fixtures

Chapter 28 Water Heaters

Chapter 29 Water Supply and Distribution

Chapter 30 Sanitary Drainage

Chapter 31 Vents

Chapter 32 Traps

Part VIII ‒ Electrical

Chapter 33 General Requirements

Chapter 34 Electrical Definitions

Chapter 35 Services

Chapter 36 Branch Circuit and Feeder Requirements

Chapter 37 Wiring Methods

Chapter 38 Power and Lighting Distribution

Chapter 39 Devices and Luminaires

Chapter 40 Appliance Installation

Chapter 41 Swimming Pools

Chapter 42 Class 2 Remote-Control‚ Signaling and Power-Limited Circuits

Part IX ‒ Referenced Standards

Chapter 43 Referenced Standards

Appendix A Sizing and Capacities of Gas Piping

Appendix B Sizing of Venting Systems Serving Appliances Equipped With Draft Hoods

Appendix C Plumbing Sanitary Drainage Fittings

Appendix D Recommended Procedure for Safety Inspection of an Existing Appliance Installation

Appendix E Manufactured Housing Used as Dwellings

Appendix F Reserved

Appendix G Swimming Pools‚ Spas and Hot Tubs

Appendix H Patio Covers

Appendix I Reserved

Appendix J Existing Buildings and Structures

Appendix K Sound Transmission

Appendix L Reserved

Appendix M Reserved

Appendix N Structural Safety

Appendix O Reserved

Appendix P Reserved

Appendix Q Reserved

The provisions of this chapter shall control the design and construction of the floors for all buildings including the floors of attic spaces used to house mechanical or plumbing fixtures and equipment.
Floor construction shall be capable of accommodating all loads according to Section R301 and of transmitting the resulting loads to the supporting structural elements.
Load-bearing dimension lumber for joists, beams and girders shall be identified by a grade mark of a lumber grading or inspection agency that has been approved by an accreditation body that complies with DOC PS 20. In lieu of a grade mark, a certificate of inspection issued by a lumber grading or inspection agency meeting the requirements of this section shall be accepted.

Exception:
Dimension lumber which is neither identified by a grade mark nor issued a certificate of inspection by a lumber grading or inspection agency may be used for load bearing purposes under the following conditions when authorized by the authority having jurisdiction:

1. The producing mill shall sell or provide the lumber directly to the ultimate consumer or the consumer’s contract builder for use in an approved structure.
2. The producing mill shall certify in writing to the consumer or contract builder on a form to be provided by the authority having jurisdiction that the quality and safe working stresses of such lumber are equal to or exceed No. 2 grade of the species in accordance with the conditions set forth in American Softwood Lumber Standard (PS 20-99) published by the United States Department of Commerce. Such certification shall be filed as part of the building permit application.
Preservative treated dimension lumber shall also be identified as required by Section R319.1.
Blocking shall be a minimum of utility grade lumber. Subflooring may be a minimum of utility grade lumber or No. 4 common grade boards.
Approved end-jointed lumber identified by a grade mark conforming to Section R502.1 may be used interchangeably with solid-sawn members of the same species and grade.
Structural capacities and design provisions for prefabricated wood I-joists shall be established and monitored in accordance with ASTM D 5055.
Glued laminated timbers shall be manufactured and identified as required in AITC A190.1 and ASTM D 3737.
Stress grading of structural log members of nonrectangular shape, as typically used in log buildings, shall be in accordance with ASTM D 3957. Such structural log members shall be identified by the grade mark of an approved lumber grading or inspection agency. In lieu of a grade mark on the material, a certificate of inspection as to species and grade issued by a lumber-grading or inspection agency meeting the requirements of this section shall be permitted to be accepted.
Floors shall be designed and constructed in accordance with the provisions of this chapter, Figure R502.2 and Sections R319 and R320 or in accordance with AF&PA;/NDS.




 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

FIGURE R502.2
FLOOR CONSTRUCTION
A load path for lateral forces shall be provided between floor framing and braced wall panels located above or below a floor, as specified in Section R602.10.8.
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. For decks with cantilevered framing members, connections to exterior walls or other framing members, shall be designed and constructed to resist uplift resulting from the full live load specified in Table R301.5 acting on the cantilevered portion of the deck.
Spans for floor joists shall be in accordance with Tables R502.3.1(1) and R502.3.1(2). For other grades and species and for other loading conditions, refer to the AF&PA; Span Tables for Joists and Rafters.
Table R502.3.1(1) shall be used to determine the maximum allowable span of floor joists that support sleeping areas and attics that are accessed by means of a fixed stairway in accordance with Section R3 11.5 provided that the design live load does not exceed 30 psf (1.44 kPa) and the design dead load does not exceed 20 psf (0.96 kPa). The allowable span of ceiling joists that support attics used for limited storage or no storage shall be determined in accordance with Section R802.4.

TABLE R502.3.1(1)
FLOOR JOIST SPANS FOR COMMON LUMBER SPECIES (Residential sleeping areas, live load = 30 psf, L/ = 360)a

JOISTSPACING (inches) SPECIES AND GRADE DEADLOAD = 10 psf       DEADLOAD = 20 psf      
2 × 6 2 × 8 2 × 10 2 × 12 2 × 6 2 × 8 2 × 10 2 × 12
Maximum floor joist spans
(ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.)
 12 Douglas fir-larch SS 12-6 16-6 21-0 25-7 12-6 16-6 21-0 25-7
Douglas fir-larch #1 12-0 15-10 20-3 24-8 12-0 15-7 19-0 22-0
Douglas fir-larch #2 11-10 15-7 19-10 23-0 11-6 14-7 17-9 20-7
Douglas fir-larch #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Hem-fir SS 11-10 15-7 19-10 24-2 11-10 15-7 19-10 24-2
Hem-fir #1 11-7 15-3 19-5 23-7 11-7 15-2 18-6 21-6
Hem-fir #2 11-0 14-6 18-6 22-6 11-0 14-4 17-6 20-4
Hem-fir #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Southern pine SS 12-3 16-2 20-8 25-1 12-3 16-2 20-8 25-1
Southern pine #1 12-0 15-10 20-3 24-8 12-0 15-10 20-3 24-8
Southern pine #2 11-10 15-7 19-10 24-2 11-10 15-7 18-7 21-9
Southern pine #3 10-5 13-3 15-8 18-8 9-4 11-11 14-0 16-8
Spruce-pine-firb SS 11-7 15-3 19-5 23-7 11-7 15-3 19-5 23-7
Spruce-pine-firb #1 11-3 14-11 19-0 23-0 11-3 14-7 17-9 20-7
Spruce-pine-firb #2 11-3 14-11 19-0 23-0 11-3 14-7 17-9 20-7
Spruce-pine-firb #3 9-8 12-4 15-0 17-5 8-8 11-0 13-5 15-7
 16 Douglas fir-larch SS 11-4 15-0 19-1 23-3 11-4 15-0 19-1 23-0
Douglas fir-larch #1 10-11 14-5 18-5 21-4 10-8 13-6 16-5 19-1
Douglas fir-larch #2 10-9 14-0 17-2 19-11 9-11 12-7 15-5 17-10
Douglas fir-larch #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
Hem-fir SS 10-9 14-2 18-0 21-11 10-9 14-2 18-0 21-11
Hem-fir #1 10-6 13-10 17-8 20-9 10-4 13-1 16-0 18-7
Hem-fir #2 10-0 13-2 16-10 19-8 9-10 12-5 15-2 17-7
Hem-fir #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
Southern pine SS 11-2 14-8 18-9 22-10 11-2 14-8 18-9 22-10
Southern pine #1 10-11 14-5 18-5 22-5 10-11 14-5 17-11 21-4
Southern pine #2 10-9 14-2 18-0 21-1 10-5 13-6 16-1 18-10
Southern pine #3 9-0 11-6 13-7 16-2 8-1 10-3 12-2 14-6
Spruce-pine-firb SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-4
Spruce-pine-firb #1 10-3 13-6 17-2 19-11 9-11 12-7 15-5 17-10
Spruce-pine-firb #2 10-3 13-6 17-2 19-11 9-11 12-7 15-5 17-10
Spruce-pine-firb #3 8-5 10-8 13-0 15-1 7-6 9-6 11-8 13-6
 19.2 Douglas fir-larch SS 10-8 14-1 18-0 21-10 10-8 14-1 18-0 21-0
Douglas fir-larch #1 10-4 13-7 16-9 19-6 9-8 12-4 15-0 17-5
Douglas fir-larch #2 10-1 12-10 15-8 18-3 9-1 11-6 14-1 16-3
Douglas fir-larch #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
Hem-fir SS 10-1 13-4 17-0 20-8 10-1 13-4 17-0 20-7
Hem-fir #1 9-10 13-0 16-4 19-0 9-6 12-0 14-8 17-0
Hem-fir #2 9-5 12-5 15-6 17-1 8-11 11-4 13-10 16-1
Hem-fir #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
Southern pine SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-6
Southern pine #1 10-4 13-7 17-4 21-1 10-4 13-7 16-4 19-6
Southern pine #2 10-1 13-4 16-5 19-3 9-6 12-4 14-8 17-2
Southern pine #3 8-3 10-6 12-5 14-9 7-4 9-5 11-1 13-2
Spruce-pine-firb SS 9-10 13-0 16-7 20-2 9-10 13-0 16-7 19-6
Spruce-pine-firb #1 9-8 12-9 15-8 18-3 9-1 11-6 14-1 16-3
Spruce-pine-firb #2 9-8 12-9 15-8 18-3 9-1 11-6 14-1 16-3
Spruce-pine-firb #3 7-8 9-9 11-10 13-9 6-10 8-8 10-7 12-4
24 Douglas fir-larch SS 9-11 13-1 16-8 20-3 9-11 13-1 16-2 18-9
Douglas fir-larch #1 9-7 12-4 15-0 17-5 8-8 11-0 13-5 15-7
Douglas fir-larch #2 9-1 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Douglas fir-larch #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0
Hem-fir SS 9-4 12-4 15-9 19-2 9-4 12-4 15-9 18-5
Hem-fir #1 9-2 12-0 14-8 17-0 8-6 10-9 13-1 15-2
Hem-fir #2 8-9 11-4 13-10 16-1 8-0 10-2 12-5 14-4
Hem-fir #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0
Southern pine SS 9-9 12-10 16-5 19-11 9-9 12-10 16-5 19-11
Southern pine #1 9-7 12-7 16-1 19-6 9-7 12-4 14-7 17-5
Southern pine #2 9-4 12-4 14-8 17-2 8-6 11-0 13-1 15-5
Southern pine #3 7-4 9-5 11-1 13-2 6-7 8-5 9-11 11-10
Spruce-pine-firb SS 9-2 12-1 15-5 18-9 9-2 12-1 15-0 17-5
Spruce-pine-firb #1 8-11 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Spruce-pine-firb #2 8-11 11-6 14-1 16-3 8-1 10-3 12-7 14-7
Spruce-pine-firb #3 6-10 8-8 10-7 12-4 6-2 7-9 9-6 11-0



For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
 
NOTE: Check sources for availability of lumber in lengths greater than 20 feet.
   
a. Dead load limits for townhouses in Seismic Design Category C and all structures in Seismic Design Categories D0, D1 and D2 shall be determined in accordance with Section R301.2.2.2.1.
   
b. North American Spruce-Pine-Fir species only.

TABLE R502.3.1(2)
FLOOR JOIST SPANS FOR COMMON LUMBER SPECIES (Residential living areas, live load = 40 psf, L/ = 360)b

JOISTSPACING (inches) SPECIES AND GRADE DEAD LOAD = 10 psf DEAD LOAD = 20 psf
2 × 6 2 × 8 2 × 10 2 × 12 2 × 6 2 × 8 2 × 10 2 × 12
Maximum floor joist spans
(ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.) (ft - in.)
12 Douglas fir-larch SS 11-4 15-0 19-1 23-3 11-4 15-0 19-1 23-3
Douglas fir-larch #1 10-11 14-5 18-5 22-0 10-11 14-2 17-4 20-1
Douglas fir-larch #2 10-9 14-2 17-9 20-7 10-6 13-3 16-3 18-10
Douglas fir-larch #3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
Hem-fir SS 10-9 14-2 18-0 21-11 10-9 14-2 18-0 21-11
Hem-fir #1 10-6 13-10 17-8 21-6 10-6 13-10 16-11 19-7
Hem-fir #2 10-0 13-2 16-10 20-4 10-0 13-1 16-0 18-6
Hem-fir #3 8-8 10-0 13-5 15-7 7-11 10-0 12-3 14-3
Southern pine SS 11-2 14-8 18-9 22-10 11-2 14-8 18-9 22-10
Southern pine #1 10-11 14-5 18-5 22-5 10-11 14-5 18-5 22-5
Southern pine #2 10-9 14-2 18-0 21-9 10-9 14-2 16-11 19-10
Southern pine #3 9-4 11-11 14-0 16-8 8-6 10-10 12-10 15-3
Spruce-pine-firc SS 10-6 13-10 17-8 21-6 10-6 13-10 17-8 21-6
Spruce-pine-firc #1 10-3 13-6 17-3 20-7 10-3 13-3 16-3 18-10
Spruce-pine-firc #2 10-3 13-6 17-3 20-7 10-3 13-3 16-3 18-10
Spruce-pine-firc #3 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
16 Douglas fir-larch SS 10-4 13-7 17-4 21-1 10-4 13-7 17-4 21-0
Douglas fir-larch #1 9-11 13-1 16-5 19-1 9-8 12-4 15-0 17-5
Douglas fir-larch #2 9-9 12-7 15-5 17-10 9-1 11-6 14-1 16-3
Douglas fir-larch #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
Hem-fir SS 9-9 12-10 16-5 19-11 9-9 12-10 16-5 19-11
Hem-fir #1 9-6 12-7 16-0 18-7 9-6 12-0 14-8 17-0
Hem-fir #2 9-1 12-0 15-2 17-7 8-11 11-4 13-10 16-1
Hem-fir #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
Southern pine SS 10-2 13-4 17-0 20-9 10-2 13-4 17-0 20-9
Southern pine #1 9-11 13-1 16-9 20-4 9-11 13-1 16-4 19-6
Southern pine #2 9-9 12-10 16-1 18-10 9-6 12-4 14-8 17-2
Southern pine #3 8-1 10-3 12-2 14-6 7-4 9-5 11-1 13-2
Spruce-pine-firc SS 9-6 12-7 16-0 19-6 9-6 12-7 16-0 19-6
Spruce-pine-firc #1 9-4 12-3 15-5 17-10 9-1 11-6 14-1 16-3
Spruce-pine-firc #2 9-4 12-3 15-5 17-10 9-1 11-6 14-1 16-3
Spruce-pine-firc #3 7-6 9-6 11-8 13-6 6-10 8-8 10-7 12-4
19.2 Douglas fir-larch SS 9-8 12-10 16-4 19-10 9-8 12-10 16-4 19-2
Douglas fir-larch #1 9-4 12-4 15-0 17-5 8-10 11-3 13-8 15-11
Douglas fir-larch #2 9-1 11-6 14-1 16-3 8-3 10-6 12-10 14-10
Douglas fir-larch #3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3
Hem-fir SS 9-2 12-1 15-5 18-9 9-2 12-1 15-5 18-9
Hem-fir #1 9-0 11-10 14-8 17-0 8-8 10-11 13-4 15-6
Hem-fir #2 8-7 11-3 13-1 16-1 8-2 10-4 12-8 14-8
Hem-fir #3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3
Southern pine SS 9-6 12-7 16-0 19-6 9-6 12-7 16-0 19-6
Southern pine #1 9-4 12-4 15-9 19-2 9-4 12-4 14-11 17-9
Southern pine #2 9-2 12-1 14-8 17-2 8-8 11-3 13-5 15-8
Southern pine #3 7-4 9-5 11-1 13-2 6-9 8-7 10-1 12-1
Spruce-pine-firc SS 9-0 11-10 15-1 18-4 9-0 11-10 15-1 17-9
Spruce-pine-firc #1 8-9 11-6 14-1 16-3 8-3 10-6 12-10 14-10
Spruce-pine-firc #2 8-9 11-6 14-1 16-3 8-3 10-6 12-10 14-10
Spruce-pine-firc #3 6-10 8-8 10-7 12-4 6-3 7-11 9-8 11-3
24 Douglas fir-larch SS 9-0 11-11 15-2 18-5 9-0 11-11 14-9 17-1
Douglas fir-larch #1 8-8 11-0 13-5 15-7 7-11 10-0 12-3 14-3
Douglas fir-larch #2 8-1 10-3 12-7 14-7 7-5 9-5 11-6 13-4
Douglas fir-larch #3 6-2 7-9 9-6 11-0 5-7 7-1 8-8 10-1
Hem-fir SS 8-6 11-3 14-4 17-5 8-6 11-3 14-4 16-10
Hem-fir #1 8-4 10-9 13-1 15-2 7-9 9-9 11-11 13-10
Hem-fir #2 7-11 10-2 12-5 14-4 7-4 9-3 11-4 13-1
Hem-fir #3 6-2 7-9 9-6 11-0 5-7 7-1 8-8 10-1
Southern pine SS 8-10 11-8 14-11 18-1 8-10 11-8 14-11 18-1
Southern pine #1 8-8 11-5 14-7 17-5 8-8 11-3 13-4 15-11
Southern pine #2 8-6 11-0 13-1 15-5 7-9 10-0 12-0 14-0
Southern pine #3 6-7 8-5 9-11 11-10 6-0 7-8 9-1 10-9
Spruce-pine-firc SS 8-4 11-0 14-0 17-0 8-4 11-0 13-8 15-11
Spruce-pine-firc #1 8-1 10-3 12-7 14-7 7-5 9-5 11-6 13-4
Spruce-pine-firc #2 8-1 10-3 12-7 14-7 7-5 9-5 11-6 13-4
Spruce-pine-firc #3 6-2 7-9 9-6 11-0 5-7 7-1 8-8 10-1



For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
 
NOTE: Check sources for availability of lumber in lengths greater than 20 feet.
   
a. End bearing length shall be increased to 2 inches.
   
b. Dead load limits for townhouses in Seismic Design Category C and all structures in Seismic Design Categories D0, D1, and D2 shall be determined in accordance with Section R301.2.2.2.1.
   
c. North American Spruce-Pine-Fir species only.
Table R502.3.1(2) shall be used to determine the maximum allowable span of floor joists that support all other areas of the building, other than sleeping rooms and attics, provided that the design live load does not exceed 40 psf (1 .92 kPa) and the design dead load does not exceed 20 psf (0.96 kPa).
Floor cantilever spans shall not exceed the nominal depth of the wood floor joist. Floor cantilevers constructed in accordance with Table R502.3.3(1) shall be permitted when supporting a light- frame bearing wall and roof only. Floor cantilevers supporting an exterior balcony are permitted to be constructed in accordance with Table R502.3.3(2).

TABLE R502.3.3(1)
CANTILEVER SPANS FOR FLOOR JOISTS SUPPORTING LIGHT-FRAME EXTERIOR BEARING WALL AND ROOF ONLYa, b, c, f, g, h(Floor Live Load ≤ 40 psf, Roof Live Load ≤ 20 psf)

Member & Spacing Maximum Cantilever Span (Uplift Force at Backspan Support in lbs.)d, e
Ground Snow Load
≤ 20 psf 30 psf 50 psf 70 psf
Roof Width Roof Width Roof Width Roof Width
24 ft 32 ft 40 ft 24 ft 32 ft 40 ft 24 ft 32 ft 40 ft 24 ft 32 ft 40 ft
2 × 8 @ 12" 20" (177) 15" (227) -— 18" (209)
2 × 10 @ 16" 29" (228) 21" (297) 16" (364) 26" (271) 18" (354) 20" (375)
2 × 10 @ 12" 36" (166) 26" (219) 20" (270) 34" (198) 22" (263) 16" (324) 26" (277) -— -— 19" (356) -— -—
2 × 12 @ 16" -— 32" (287) 25" (356) 36" (263) 29" (345) 21" (428) 29" (367) 20" (484) -— 23" (471) -— -—
2 × 12 @ 12" -— 42" (209) 31" (263) -— 37" (253) 27" (317) 36" (271) 27" (358) 17" (447) 31" (348) 19" (462) -—
2 × 12 @ 8" -— 48" (136) 45" (169) -— 48" (164) 38" (206) -— 40" (233) 26" (294) 36" (230) 29" (304) 18" (379)



For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
a. Tabulated values are for clear-span roof supported solely by exterior bearing walls.
b. Spans are based on No. 2 Grade lumber of Douglas fir-larch, hem-fir, southern pine, and spruce-pine-fir for repetitive (3 or more) members.
c. Ratio of backspan to cantilever span shall be at least 3:1.
d. Connections capable of resisting the indicated uplift force shall be provided at the backspan support.
e. Uplift force is for a backspan to cantilever span ratio of 3:1. Tabulated uplift values are permitted to be reduced by multiplying by a factor equal to 3 divided by the actual backspan ratio provided (3/backspan ratio).
f. See Section R301.2.2.2.2, Item 1, for additional limitations on cantilevered floor joists for detached one- and two-family dwellings in Seismic Design Category D0, D1, or D2 and townhouses in Seismic Design Category C, D0, D1, or D2.
g. A full-depth rim joist shall be provided at the cantilevered end of the joists. Solid blocking shall be provided at the cantilever support.
h. Linear interpolation shall be permitted for building widths and ground snow loads other than shown.

TABLE R502.3.3(2)
CANTILEVER SPANS FOR FLOOR JOISTS SUPPORTING EXTERIOR BALCONYa, b, e, f

Member Size Spacing  Maximum Cantilever Span (Uplift Force at Backspan Support in lbs.)c, d  
 Ground Snow Load
≤ 30 psf 50 psf 70 psf
2 × 8 12" 42" (139) 39" (156) 34" (165)
2 × 8 16" 36" (151) 34" (171) 29" (180)
2 × 10 12" 61" (164) 57" (189) 49" (201)
2 × 10 16" 53" (180) 49" (208) 42" (220)
2 × 10 24" 43" (212) 40" (241) 34" (255)
2 × 12 16" 72" (228) 67" (260) 57" (268)
2 × 12 24" 58" (279) 54" (319) 47" (330)



For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Spans are based on No. 2 Grade lumber of Douglas fir-larch, hem-fir, southern pine, and spruce-pine-fir for repetitive (3 or more) members.
   
b. Ratio of backspan to cantilever span shall be at least 2:1.
   
c. Connections capable of resisting the indicated uplift force shall be provided at the backspan support.
   
d. Uplift force is for a backspan to cantilever span ratio of 2:1. Tabulated uplift values are permitted to be reduced by multiplying by a factor equal to 2 divided by the actual backspan ratio provided (2/backspan ratio).
   
e. A full-depth rim joist shall be provided at the cantilevered end of the joists. Solid blocking shall be provided at the cantilevered support.
   
f. Linear interpolation shall be permitted for ground snow loads other than shown.
Joists under parallel bearing partitions shall be of adequate size to support the load. Double joists, sized to adequately support the load, that are separated to permit the installation of piping or vents shall be full depth solid blocked with lumber not less than 2 inches (51 mm) in nominal thickness spaced not more than 4 feet (1219 mm) on center. Bearing partitions perpendicular to joists shall not be offset from supporting girders, walls or partitions more than the joist depth unless such joists are of sufficient size to carry the additional load.
The allowable spans of girders fabricated of dimension lumber shall not exceed the values set forth in Tables R502.5(1) and R502.5(2).

TABLE R502.5(1)
GIRDER SPANSa AND HEADER SPANSa FOR EXTERIOR BEARING WALLS (Maximum spans for Douglas fir-larch, hem-fir, southern pine and spruce-pine-firb and required number of jack studs)

GIRDERS AND HEADERS SUP-
PORTING
SIZE GROUND SNOW LOAD (psf)e
30 50 70
Building widthc(feet)
20 28 36 20 28 36 20 28 36
Span NJd Span NJd Span NJd Span NJd Span NJd Span NJd Span NJd Span NJd Span NJd
Roof and ceiling 2-2x4 3-6 1 3-2 1 2-10 1 3-2 1 2-9 1 2-6 1 2-10 1 2-6 1 2-3 1
2-2x6 5-5 1 4-8 1 4-2 1 4-8 1 4-1 1 3-8 2 4-2 1 3-8 2 3-3 2
2-2x8 6-10 1 5-11 2 5-4 2 5-11 2 5-2 2 4-7 2 5-4 2 4-7 2 4-1 2
2-2x10 8-5 2 7-3 2 6-6 2 7-3 2 6-3 2 5-7 2 6-6 2 5-7 2 5-0 2
2-2x12 9-9 2 8-5 2 7-6 2 8-5 2 7-3 2 6-6 2 7-6 2 6-6 2 5-10 3
3-2x8 8-4 1 7-5 1 6-8 1 7-5 1 6-5 2 5-9 2 6-8 1 5-9 2 5-2 2
3-2x10 10-6 1 9-1 2 8-2 2 9-1 2 7-10 2 7-0 2 8-2 2 7-0 2 6-4 2
3-2x12 12-2 2 10-7 2 9-5 2 10-7 2 9-2 2 8-2 2 9-5 2 8-2 2 7-4 2
4-2x8 9-2 1 8-4 1 7-8 1 8-4 1 7-5 1 6-8 1 7-8 1 6-8 1 5-11 2
4-2x10 11-8 1 10-6 1 9-5 2 10-6 1 9-1 2 8-2 2 9-5 2 8-2 2 7-3 2
4-2x12 14-1 1 12-2 2 10-11 2 12-2 2 10-7 2 9-5 2 10-11 2 9-5 2 8-5 2
Roof, ceiling
and one center-bearing floor
2-2x4 3-1 1 2-9 1 2-5 1 2-9 1 2-5 1 2-2 1 2-7 1 2-3 1 2-0 1
2-2x6 4-6 1 4-0 1 3-7 2 4-1 1 3-7 2 3-3 2 3-9 2 3-3 2 2-11 2
2-2x8 5-9 2 5-0 2 4-6 2 5-2 2 4-6 2 4-1 2 4-9 2 4-2 2 3-9 2
2-2x10 7-0 2 6-2 2 5-6 2 6-4 2 5-6 2 5-0 2 5-9 2 5-1 2 4-7 3
2-2x12 8-1 2 7-1 2 6-5 2 7-4 2 6-5 2 5-9 3 6-8 2 5-10 3 5-3 3
3-2x8 7-2 1 6-3 2 5-8 2 6-5 2 5-8 2 5-1 2 5-11 2 5-2 2 4-8 2
3-2x10 8-9 2 7-8 2 6-11 2 7-11 2 6-11 2 6-3 2 7-3 2 6-4 2 5-8 2
3-2x12 10-2 2 8-11 2 8-0 2 9-2 2 8-0 2 7-3 2 8-5 2 7-4 2 6-7 2
4-2x8 8-1 1 7-3 1 6-7 1 7-5 1 6-6 1 5-11 2 6-10 1 6-0 2 5-5 2
4-2x10 10-1 1 8-10 2 8-0 2 9-1 2 8-0 2 7-2 2 8-4 2 7-4 2 6-7 2
4-2x12 11-9 2 10-3 2 9-3 2 10-7 2 9-3 2 8-4 2 9-8 2 8-6 2 7-7 2
Roof, ceiling
and one clear span floor
2-2x4 2-8 1 2-4 1 2-1 1 2-7 1 2-3 1 2-0 1 2-5 1 2-1 1 1-10 1
2-2x6 3-11 1 3-5 2 3-0 2 3-10 2 3-4 2 3-0 2 3-6 2 3-1 2 2-9 2
2-2x8 5-0 2 4-4 2 3-10 2 4-10 2 4-2 2 3-9 2 4-6 2 3-11 2 3-6 2
2-2x10 6-1 2 5-3 2 4-8 2 5-11 2 5-1 2 4-7 3 5-6 2 4-9 2 4-3 3
2-2x12 7-1 2 6-1 3 5-5 3 6-10 2 5-11 3 5-4 3 6-4 2 5-6 3 5-0 3
3-2x8 6-3 2 5-5 2 4-10 2 6-1 2 5-3 2 4-8 2 5-7 2 4-11 2 4-5 2
3-2x10 7-7 2 6-7 2 5-11 2 7-5 2 6-5 2 5-9 2 6-10 2 6-0 2 5-4 2
3-2x12 8-10 2 7-8 2 6-10 2 8-7 2 7-5 2 6-8 2 7-11 2 6-11 2 6-3 2
4-2x8 7-2 1 6-3 2 5-7 2 7-0 1 6-1 2 5-5 2 6-6 1 5-8 2 5-1 2
4-2x10 8-9 2 7-7 2 6-10 2 8-7 2 7-5 2 6-7 2 7-11 2 6-11 2 6-2 2
4-2x12 10-2 2 8-10 2 7-11 2 9-11 2 8-7 2 7-8 2 9-2 2 8-0 2 7-2 2
Roof, ceiling
and two center-bearing floors
2-2x4 2-7 1 2-3 1 2-0 1 2-6 1 2-2 1 1-11 1 2-4 1 2-0 1 1-9 1
2-2x6 3-9 2 3-3 2 2-11 2 3-8 2 3-2 2 2-10 2 3-5 2 3-0 2 2-8 2
2-2x8 4-9 2 4-2 2 3-9 2 4-7 2 4-0 2 3-8 2 4-4 2 3-9 2 3-5 2
2-2x10 5-9 2 5-1 2 4-7 3 5-8 2 4-11 2 4-5 3 5-3 2 4-7 3 4-2 3
2-2x12 6-8 2 5-10 3 5-3 3 6-6 2 5-9 3 5-2 3 6-1 3 5-4 3 4-10 3
3-2x8 5-11 2 5-2 2 4-8 2 5-9 2 5-1 2 4-7 2 5-5 2 4-9 2 4-3 2
3-2x10 7-3 2 6-4 2 5-8 2 7-1 2 6-2 2 5-7 2 6-7 2 5-9 2 5-3 2
3-2x12 8-5 2 7-4 2 6-7 2 8-2 2 7-2 2 6-5 3 7-8 2 6-9 2 6-1 3
4-2x8 6-10 1 6-0 2 5-5 2 6-8 1 5-10 2 5-3 2 6-3 2 5-6 2 4-11 2
4-2x10 8-4 2 7-4 2 6-7 2 8-2 2 7-2 2 6-5 2 7-7 2 6-8 2 6-0 2
4-2x12 9-8 2 8-6 2 7-8 2 9-5 2 8-3 2 7-5 2 8-10 2 7-9 2 7-0 2
Roof, ceiling,
and two clear span floors
2-2x4 2-1 1 1-8 1 1-6 2 2-0 1 1-8 1 1-5 2 2-0 1 1-8 1 1-5 2
2-2x6 3-1 2 2-8 2 2-4 2 3-0 2 2-7 2 2-3 2 2-11 2 2-7 2 2-3 2
2-2x8 3-10 2 3-4 2 3-0 3 3-10 2 3-4 2 2-11 3 3-9 2 3-3 2 2-11 3
2-2x10 4-9 2 4-1 3 3-8 3 4-8 2 4-0 3 3-7 3 4-7 3 4-0 3 3-6 3
2-2x12 5-6 3 4-9 3 4-3 3 5-5 3 4-8 3 4-2 3 5-4 3 4-7 3 4-1 4
3-2x8 4-10 2 4-2 2 3-9 2 4-9 2 4-1 2 3-8 2 4-8 2 4-1 2 3-8 2
3-2x10 5-11 2 5-1 2 4-7 3 5-10 2 5-0 2 4-6 3 5-9 2 4-11 2 4-5 3
3-2x12 6-10 2 5-11 3 5-4 3 6-9 2 5-10 3 5-3 3 6-8 2 5-9 3 5-2 3
4-2x8 5-7 2 4-10 2 4-4 2 5-6 2 4-9 2 4-3 2 5-5 2 4-8 2 4-2 2
4-2x10 6-10 2 5-11 2 5-3 2 6-9 2 5-10 2 5-2 2 6-7 2 5-9 2 5-1 2
4-2x12 7-11 2 6-10 2 6-2 3 7-9 2 6-9 2 6-0 3 7-8 2 6-8 2 5-11 3

 

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Spans are given in feet and inches.
   
b. Tabulated values assume #2 grade lumber.
   
c. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
   
d. NJ - Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
   
e. Use 30 psf ground snow load for cases in which ground snow load is less than 30 psf and the roof live load is equal to or less than 20 psf.

TABLE R502.5(2)
GIRDER SPANSa AND HEADER SPANSa FOR INTERIOR BEARING WALLS (Maximum spans for Douglas fir-larch, hem-fir, southern pine and spruce-pine-firb and required number of jack studs)

HEADERS AND GIRDERS SUPPORTING SIZE BUILDING WIDTHc (feet)
20 28 36
Span NJd Span NJd Span NJd
One floor only 2-2 × 4 3-1 1 2-8 1 2-5 1
2-2 × 6 4-6 1 3-11 1 3-6 1
2-2 × 8 5-9 1 5-0 2 4-5 2
2-2 × 10 7-0 2 6-1 2 5-5 2
2-2 × 12 8-1 2 7-0 2 6-3 2
3-2 × 8 7-2 1 6-3 1 5-7 2
3-2 × 10 8-9 1 7-7 2 6-9 2
3-2 × 12 10-2 2 8-10 2 7-10 2
4-2 × 8 9-0 1 7-8 1 6-9 1
4-2 × 10 10-1 1 8-9 1 7-10 2
4-2 × 12 11-9 1 10-2 2 9-1 2
Two floors 2-2 × 4 2-2 1 1-10 1 1-7 1
2-2 × 6 3-2 2 2-9 2 2-5 2
2-2 × 8 4-1 2 3-6 2 3-2 2
2-2 × 10 4-11 2 4-3 2 3-10 3
2-2 × 12 5-9 2 5-0 3 4-5 3
3-2 × 8 5-1 2 4-5 2 3-11 2
3-2 × 10 6-2 2 5-4 2 4-10 2
3-2 × 12 7-2 2 6-3 2 5-7 3
4-2 × 8 6-1 1 5-3 2 4-8 2
4-2 × 10 7-2 2 6-2 2 5-6 2
4-2 × 12 8-4 2 7-2 2 6-5 2

 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
a. Spans are given in feet and inches.
b. Tabulated values assume #2 grade lumber.
c. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
d. NJ - Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an approved framing anchor attached to the full-height wall stud and to the header.
The ends of each joist, beam or girder shall have not less than 1.5 inches (38 mm) of bearing on wood or metal and not less than 3 inches (76 mm) on masonry or concrete except where supported on a 1-inch-by-4-inch (25.4 mm by 102 mm) ribbon strip and nailed to the adjacent stud or by the use of approved joist hangers.
Joists framing from opposite sides over a bearing support shall lap a minimum of 3 inches (76 mm) and shall be nailed together with a minimum three 10d face nails. A wood or metal splice with strength equal to or greater than that provided by the nailed lap is permitted.
Joists framing into the side of a wood girder shall be supported by approved framing anchors or on ledger strips not less than nominal 2 inches by 2 inches (51 mm by 51 mm).
Joists shall be supported laterally at the ends by full-depth solid blocking not less than 2 inches (51 mm) nominal in thickness; or by attachment to a full-depth header, band or rim joist, or to an adjoining stud or shall be otherwise provided with lateral support to prevent rotation.

Exception:
In Seismic Design Categories D0, D1 and D2, lateral restraint shall also be provided at each intermediate support.
Joists exceeding a nominal 2 inches by 12 inches (51 mm by 305 mm) shall be supported laterally by solid blocking, diagonal bridging (wood or metal), or a continuous 1-inch-by-3-inch (25.4 mm by 76 mm) strip nailed across the bottom of joists perpendicular to joists at intervals not exceeding 8 feet (2438 mm).
Structural floor members shall not be cut, bored or notched in excess of the limitations specified in this section. See Figure R502.8.

 











For SI: 1 inch = 25.4 mm.

FIGURE R502.8
CUTTING, NOTCHING AND DRILLING
Notches in solid lumber joists, rafters and beams shall not exceed one-sixth of the depth of the member, shall not be longer than one-third of the depth of the member and shall not be located in the middle one-third of the span. Notches at the ends of the member shall not exceed one-fourth the depth of the member. The tension side of members 4 inches (102 mm) or greater in nominal thickness shall not be notched except at the ends of the members. The diameter of holes bored or cut into members shall not exceed one-third the depth of the member. Holes shall not be closer than 2 inches (51 mm) to the top or bottom of the member, or to any other hole located in the member. Where the member is also notched, the hole shall not be closer than 2 inches (51 mm) to the notch.
Cuts, notches and holes bored in trusses, structural composite lumber, structural glue-laminated members or I-joists are prohibited except where permitted by the manufacturer’s recommendations or where the effects of such alterations are specifically considered in the design of the member by a registered design professional.
Floor framing shall be nailed in accordance with Table R602.3(1). Where posts and beam or girder construction is used to support floor framing, positive connections shall be provided to ensure against uplift and lateral displacement.
Openings in floor framing shall be framed with a header and trimmer joists. When the header joist span does not exceed 4 feet (1219 mm), the header joist may be a single member the same size as the floor joist. Single trimmer joists may be used to carry a single header joist that is located within 3 feet (914 mm) of the trimmer joist bearing. When the header joist span exceeds 4 feet (1219 mm), the trimmer joists and the header joist shall be doubled and of sufficient cross section to support the floor joists framing into the header. Approved hangers shall be used for the header joist to trimmer joist connections when the header joist span exceeds 6 feet (1829 mm). Tail joists over 12 feet (3658 mm) long shall be supported at the header by framing anchors or on ledger strips not less than 2 inches by 2 inches (51 mm by 51 mm).
Wood trusses shall be designed in accordance with standard engineering practice. The design and manufacture of metal plate connected wood trusses shall comply with ANSI/TPI 1. The truss design drawings shall be prepared by a registered design professional.
Trusses shall be braced to prevent rotation and provide lateral stability in accordance with the requirements specified in the construction documents for the building and on the individual truss design drawings. In the absence of specific bracing requirements, trusses shall be braced in accordance with the Building Component Safety Information (BCSI 1-03) Guide to Good Practice for Handling, Installing & Bracing of Metal Plate Connected Wood Trusses.
Truss members and components shall not be cut, notched, spliced or otherwise altered in any way without the approval of a registered design professional. Alterations resulting in the addition of load (e.g., HVAC equipment, water heater, etc.), that exceed the design load for the truss, shall not be permitted without verification that the truss is capable of supporting the additional loading.
Truss design drawings, prepared in compliance with Section R502.11.1, shall be submitted to the building official and approved prior to installation. Truss design drawings shall be provided with the shipment of trusses delivered to the job site. Truss design drawings shall include, at a minimum, the information specified below:
1. Slope or depth, span and spacing.
2. Location of all joints.
3. Required bearing widths.
4. Design loads as applicable:
4.1. Top chord live load;
4.2. Top chord dead load;
4.3. Bottom chord live load;
4.4. Bottom chord dead load;
4.5. Concentrated loads and their points of application; and
4.6. Controlling wind and earthquake loads.
5. Adjustments to lumber and joint connector design values for conditions of use.
6. Each reaction force and direction.
7. Joint connector type and description, e.g., size, thickness or gauge, and the dimensioned location of each joint connector except where symmetrically located relative to the joint interface.
8. Lumber size, species and grade for each member.
9. Connection requirements for:
9.1. Truss-to-girder-truss;
9.2. Truss ply-to-ply; and
9.3. Field splices.
10. Calculated deflection ratio and/or maximum description for live and total load.
11. Maximum axial compression forces in the truss members to enable the building designer to design the size, connections and anchorage of the permanent continuous lateral bracing. Forces shall be shown on the truss drawing or on supplemental documents.
12. Required permanent truss member bracing location.
When 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.
Draftstopping materials shall not be less than 1 / 2 -inch (12.7 mm) gypsum board, 3 / 8 -inch (9.5 mm) wood structural panels, 3 / 8 -inch (9.5 mm) Type 2-M-W particleboard 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 all draftstops shall be maintained.
Fireblocking shall be provided in accordance with Section R602.8.
Maximum allowable spans for lumber used as floor sheathing shall conform to Tables R503.1, R503.2.1.1(1) and R503.2.1.1(2).

TABLE R503.1
MINIMUM THICKNESS OF LUMBER FLOOR SHEATHING

JOIST OR BEAM SPACING (inches) MINIMUM NET THICKNESS
Perpendicular to joist Diagonal to joist
24 11/16 3/4
16 5/8 5/8
48a 11/2 T & G N/A
54b
60c

 

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 6.895 kPa.
   
a. For this support spacing, lumber sheathing shall have a minimum Fb of 675 and minimum E of 1,100,000 (see AF&PA/NDS).
   
b. For this support spacing, lumber sheathing shall have a minimum Fb of 765 and minimum E of 1,400,000 (see AF&PA/NDS).
   
c. For this support spacing, lumber sheathing shall have a minimum Fb of 855 and minimum E of 1,700,000 (see AF&PA/NDS).
End joints in lumber used as sub- flooring shall occur over supports unless end-matched lumber is used, in which case each piece shall bear on at least two joists. Subflooring may be omitted when joist spacing does not exceed 16 inches (406 mm) and a 1-inch (25.4 mm) nominal tongue-and-groove wood strip flooring is applied perpendicular to the joists.
Wood structural panel sheathing used for structural purposes shall conform to DOC PS 1, DOC PS 2 or, when manufactured in Canada, CSA 0437 or CSA 0325. All panels shall be identified by a grade mark of certificate of inspection issued by an approved agency.
Where used as subflooring or combination subfloor underlayment, wood structural panels shall be of one of the grades specified in Table R503.2.1.1(1). When sanded plywood is used as combination subfloor underlayment, the grade shall be as specified in Table R503.2.1 .1(2).

TABLE R503.2.1.1(1)
ALLOWABLE SPANS AND LOADS FOR WOOD STRUCTURAL PANELS FOR ROOF AND SUBFLOOR SHEATHING AND COMBINATIONSUBFLOOR UNDERLAYMENTa, b, c

SPAN RATING MINIMUM NOMINAL PANEL THICKNESS (inch) ALLOWABLE LIVE LOAD (psf)h, I MAXIMUM SPAN (inches) LOAD
(pounds per square
foot, at maximum span)
MAXIMUM SPAN (inches)
SPAN @ 16" o.c. SPAN @ 24" o.c. With edge supportd Without edge support Total load Live load
Sheathinge     Rooff Subfloorj
12/0 5/16 12 12 40 30 0
16/0 5/16 30 16 16 40 30 0
20/0 5/16 50 20 20 40 30 0
24/0 3/8 100 30 24 20g 40 30 0
24/16 7/16 100 40 24 24 50 40 16
32/16 15/32, 1/2 180 70 32 28 40 30 16h
40/20 19/32, 5/8 305 130 40 32 40 30 20h,i
48/24 23/32, 3/4 175 48 36 45 35 24
60/32 7/8   —305 60 48 45 35 32
Underlayment, C-C plugged, single floore Rooff Combination subfloor underlaymentk
16 o.c. 19/32, 5/8 100 40 24 24 50 40 16i
20 o.c. 19/32, 5/8 150 60 32 32 40 30 20i,j
24 o.c. 23/32, 3/4 240 100 48 36 35 25 24
32 o.c. 7/8   —185 48 40 50 40 32
48 o.c. 13/32, 11/8 290 60 48 50 40 48



For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
   
a. The allowable total loads were determined using a dead load of 10 psf. If the dead load exceeds 10 psf, then the live load shall be reduced accordingly.
   
b. Panels continuous over two or more spans with long dimension perpendicular to supports. Spans shall be limited to values shown because of possible effect of concentrated loads.
   
c. Applies to panels 24 inches or wider.
   
d. Lumber blocking, panel edge clips (one midway between each support, except two equally spaced between supports when span is 48 inches), tongue-and-groove panel edges, or other approved type of edge support.
   
e. Includes Structural 1 panels in these grades.
   
f. Uniform load deflection limitation: 1/180 of span under live load plus dead load, 1/240 of span under live load only.
   
g. Maximum span 24 inches for 15/32-and 1/2-inch panels.
   
h. Maximum span 24 inches where 3/4-inch wood finish flooring is installed at right angles to joists.


i. Maximum span 24 inches where 1.5 inches of lightweight concrete or approved cellular concrete is placed over the subfloor.
   
j. Unsupported edges shall have tongue-and-groove joints or shall be supported with blocking unless minimum nominal 1/4-inch thick underlayment with end and edge joints offset at least 2 inches or 1.5 inches of lightweight concrete or approved cellular concrete is placed over the subfloor, or 3/4-inch wood finish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf.
   
k. Unsupported edges shall have tongue-and-groove joints or shall be supported by blocking unless nominal 1/4-inch-thick underlayment with end and edge joints offset at least 2 inches or 3/4-inch wood finish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf, except panels with a span rating of 48 on center are limited to 65 psf total uniform load at maximum span.
   
l. Allowable live load values at spans of 16" o.c. and 24" o.c taken from reference standard APA E30, APA Engineered Wood Construction Guide. Refer to reference standard for allowable spans not listed in the table.

TABLE R503.2.1.1(2)
ALLOWABLE SPANS FOR SANDED PLYWOOD COMBINATIONSUBFLOOR UNDERLAYMENTa

IDENTIFICATION SPACING OF JOISTS (inches)
16 20 24
Species groupb
1 1/2 5/8 3/4
2, 3 5/8 3/4 7/8
4 3/4 7/8 1



For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Plywood continuous over two or more spans and face grain perpendicular to supports. Unsupported edges shall be tongue-and-groove or blocked except where nominal 1/4-inch-thick underlayment or 3/4-inch wood finish floor is used. Allowable uniform live load at maximum span based on deflection of 1/360 of span is 100 psf.
   
b. Applicable to all grades of sanded exterior-type plywood.
The maximum allowable span for wood structural panels used as subfloor or combination subfloor underlayment shall be as set forth in Table R503.2.1.1(1), or APA E30. The maximum span for sanded plywood combination subfloor underlayment shall be as set forth in Table R503.2.1.1(2).
Wood structural panels used as subfloor or combination subfloor underlayment shall be attached to wood framing in accordance with Table R602.3(1) and shall be attached to cold-formed steel framing in accordance with Table R505.3.1(2).
Particleboard shall conform to ANSI A208.1 and shall be so identified by a grade mark or certificate of inspection issued by an approved agency.
Particleboard floor underlayment shall conform to Type PBU and shall not be less than 1 / 4 inch (6.4 mm) in thickness.
Particleboard underlayment shall be installed in accordance with the recommendations of the manufacturer and attached to framing in accordance with Table R602.3(1).
Pressure-preservatively-treated wood basement floors and floors on ground shall be designed to withstand axial forces and bending moments resulting from lateral soil pressures at the base of the exterior walls and floor live and dead loads. Floor framing shall be designed to meet joist deflection requirements in accordance with Section R301.
Unless special provision is made to resist sliding caused by unbalanced lateral soil loads, wood basement floors shall be limited to applications where the differential depth of fill on opposite exterior foundation walls is 2 feet (610 mm) or less.
Joists in wood basement floors shall bear tightly against the narrow face of studs in the foundation wall or directly against a band joist that bears on the studs. Plywood subfloor shall be continuous over lapped joists or over butt joints between in-line joists. Sufficient blocking shall be provided between joists to transfer lateral forces at the base of the end walls into the floor system.
Where required, resistance to uplift or restraint against buckling shall be provided by interior bearing walls or properly designed stub walls anchored in the supporting soil below.
The area within the foundation walls shall have all vegetation, topsoil and foreign material removed, and any fill material that is added shall be free of vegetation and foreign material. The fill shall be compacted to assure uniform support of the pressure-preservativelytreated wood floor sleepers.
A minimum 4-inch-thick (102 mm) granular base of gravel having a maximum size of 3 / 4 inch (19.1 mm) or crushed stone having a maximum size of 1 / 2 inch (12.7 mm) shall be placed over the compacted earth.
Polyethylene sheeting of minimum 6-mil (0.15 mm) thickness shall be placed over the granular base. Joints shall be lapped 6 inches (152 mm) and left unsealed. The polyethylene membrane shall be placed over the pressure-preservatively-treated wood sleepers and shall not extend beneath the footing plates of the exterior walls.
All framing materials, including sleepers, joists, blocking and plywood subflooring, shall be pressure- preservative treated and dried after treatment in accordance with AWPA U1 (Commodity Specification A, Use Category 4B and section 5.2), and shall bear the label of an accredited agency.
Elements shall be straight and free of any defects that would significantly affect structural performance. Cold-formed steel floor framing members shall comply with the requirements of this section.
The provisions of this section shall control the construction of steel floor framing for buildings not greater than 60 feet (18,288 mm) in length perpendicular to the joist span, not greater than 40 feet (12 192 mm) in width parallel to the joist span, and not greater than two stories in height. Steel floor framing constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum design wind speed of 110 miles per hour (49 m/s), Exposure A, B, or C, and a maximum ground snow load of 70 psf (3.35 kPa).
When supported by steel- framed walls in accordance with Section R603, steel floor framing shall be constructed with floor joists located directly in-line with load-bearing studs located below the joists with a maximum tolerance of 3 / 4 inch (19.1 mm) between the center lines of the joist and the stud.
The design, quality assurance, installation and testing of cold-formed steel trusses shall be in accordance with the AISI Standard for Cold-formed Steel Framing-Truss Design (COFS/Truss). Truss members shall not be notched, cut or altered in any manner without an approved design.
Load-bearing floor framing members shall comply with Figure R505.2(1) and with the dimensional and minimum thickness requirements specified in Tables R505.2(1) and R505.2(2). Tracks shall comply with Figure R505.2(2) and shall have a minimum flange width of 11/4 inches (32 mm). The maximum inside bend radius for members shall be the larger of 3/32 inch (2.4 mm) or twice the uncoated steel thickness. Holes in joist webs shall comply with all of the following conditions:

1. Holes shall conform to Figure R505.2(3);
2. Holes shall be permitted only along the centerline of the web of the framing member;
3. Holes shall have a center-to-center spacing of not less than 24 inches (610 mm);
4. Holes shall have a web hole width not greater than 0.5 times the member depth, or 21/2 inches (64.5 mm);
5. Holes shall have a web hole length not exceeding 41/2 inches (114 mm); and
6. Holes shall have a minimum distance between the edge of the bearing surface and the edge of the web hole of not less than 10 inches (254 mm).
7. Framing members with web holes not conforming to the above requirements shall be patched in accordance with Section R505.3.6 or designed in accordance with accepted engineering practices.

TABLE R505.2(1) COLD-FORMED STEEL JOIST SIZES


MEMBER
DESIGNATIONa
WEB DEPTH (inches) MINIMUM FLANGE WIDTH (inches) MAXIMUM FLANGE WIDTH (inches) MINIMUM LIP SIZE (inches)
550S162-t 5.5 1.625 2 0.5
800S162-t 8 1.625 2 0.5
1000S162-t 10 1.625 2 0.5
1200S162-t 12 1.625 2 0.5

 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm.
   
a. The member designation is defined by the first number representing the member depth in 0.01 inch, the letter "S" representing a stud or joist member, the second number representing the flange width in 0.01 inch, and the letter "t" shall be a number representing the minimum base metal thickness in mils [See Table R505.2(2)].

TABLE R505.2(2)
MINIMUM THICKNESS OF COLD-FORMED STEEL MEMBERS

DESIGNATION
(mils)
MINIMUM UNCOATED THICKNESS (inches) REFERENCE GAGE NUMBER
33 0.033 20
43 0.043 18
54 0.054 16
68 0.068 14

 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm.

 




 FIGURE R505.2(1) C-SECTION




 FIGURE R505.2(2) TRACK SECTION

 




 

For SI: 1 inch = 25.4 mm.

FIGURE R505.2(3)
FLOOR JOIST WEB HOLES
Load-bearing members used in steel floor construction shall be cold-formed to shape from structural quality sheet steel complying with the requirements of one of the following:
1. ASTM A 653: Grades 33, 37, 40 and 50 (Class 1 and 3).
2. ASTM A 792: Grades 33, 37, 40 and 50A.
3. ASTM A 875: Grades 33, 37, 40 and 50 (Class 1 and 3).
4. ASTM A 1003: Grades 33, 37, 40 and 50.
Load-bearing steel framing members shall have a legible label, stencil, stamp or embossment with the following information as a minimum:
1. Manufacturer’s identification.
2. Minimum uncoated steel thickness in inches (mm).
3. Minimum coating designation.
4. Minimum yield strength, in kips per square inch (ksi) (kPa).
Load-bearing steel framing shall have a metallic coating complying with one of the following:
1. A minimum of G 60 in accordance with ASTM A 653.
2. A minimum of AZ 50 in accordance with ASTM A 792.
3. A minimum of GF 60 in accordance with ASTM A 875.
Screws for steel-tosteel connections shall be installed with a minimum edge distance and center-to-center spacing of 0.5 inch (12.7 mm), shall be self-drilling tapping, and shall conform to SAE J78. Floor sheathing shall be attached to steel joists with minimum No. 8 self-drilling tapping screws that conform to SAE J78. Screws attaching floor-sheathing-tosteel joists shall have a minimum head diameter of 0.292 inch (7.4 mm) with countersunk heads and shall be installed with a minimum edge distance of 0.375 inch (9.5 mm). Gypsum board ceilings shall be attached to steel joists with minimum No. 6 screws conforming to ASTM C 954 and shall be installed in accordance with Section R702. For all connections, screws shall extend through the steel a minimum of three exposed threads. All self-drilling tapping screws conforming to SAE J78 shall have a Type II coating in accordance with ASTM B 633.

Where No. 8 screws are specified in a steel to steel connection the required number of screws in the connection is permitted to be reduced in accordance with the reduction factors in Table R505.2.4 when larger screws are used or when one of the sheets of steel being connected is thicker than 33 mils (0.84 mm). When applying the reduction factor the resulting number of screws shall be rounded up.

TABLE R505.2.4
SCREW SUBSTITUTION FACTOR

SCREW SIZE THINNEST CONNECTED STEEL SHEET (mils)
33 43
#8 1.0 0.67
#10 0.93 0.62
#12 0.86 0.56



For SI: 1 mil = 0.0254 mm.
505.3 Floor construction. Cold-formed steel floors shall be constructed in accordance with this section and Figure R505.3.




 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

FIGURE R505.3
STEEL FLOOR CONSTRUCTION

(continued)








For SI: 1inch = 25.4 mm, 1 mil = 0.0254 mm.

FIGURE R505.3—continued
STEEL FLOOR CONSTRUCTION
505.3.1 Floor to foundation or bearing wall connections. Cold-formed steel floors shall be anchored to foundations, wood sills or load-bearing walls in accordance with Table R505.3.1(1) and Figure R505.3.1(1), R505.3.1(2), R505.3.1(3), R505.3.1(4), R505.3.1(5) or R505.3.1(6). Continuous steel joists supported by interior load-bearing walls shall be constructed in accordance with Figure R505.3.1(7). Lapped steel joists shall be constructed in accordance with Figure R505.3.1(8). Fastening of steel joists to other framing members shall be in accordance with Table R505.3.1(2).

TABLE R505.3.1(1)FLOOR TO FOUNDATION OR BEARING WALL CONNECTION REQUIREMENTS a, b


FRAMING CONDITION WIND SPEED (mph) AND EXPOSURE
Up to 110 A/B or 85 C or Seismic Design
Categories A, B, C
Up to 110 C
Floor joist to wall track of exterior steel
load-bearing wall per Figure R505.3.1(1)
2-No. 8 screws 3-No. 8 screws
Floor joist track to wood sill per Figure
R505.3. 1(2)
Steel plate spaced at 3´ o.c., with 4-No. 8
screws and 4-10d or 6-8d common nails
Steel plate, spaced at 2´ o.c., with 4-No. 8
screws and 4-10d or 6-8d common nails
Floor joist track to foundation per Figure
 R505.3.1(3)
1/2 " minimum diameter anchor bolt and clip
angle spaced at 6´ o.c. with 8-No. 8 screws
1/2" minimum diameter anchor bolt and clip
angle spaced at 4´ o.c. with 8-No. 8 screws
Joist cantilever to wall track per Figure
R505.3. 1(4)
2-No. 8 screws per stiffener or bent plate 3-No. 8 screws per stiffener or bent plate
Joist cantilever to wood sill per Figure
R505.3. 1(5)
Steel plate spaced at 3´ o.c., with 4-No. 8
screws and 4-10d or 6-8d common nails
Steel plate spaced at 2´ o.c., with 4-No. 8
screws and 4-10d or 6-8d common nails
Joist cantilever to foundation per Figure
R505.3.1(6)
1/2" minimum diameter anchor bolt and clip
angle spaced at 6´ o.c. with 8-No. 8 screws
1/2" minimum diameter anchor bolt and clip
angle spaced at 4´ o.c. with 8-No. 8 screws

 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 mile per hour = 0.447 m/s.
   
a. Anchor bolts shall be located not more than 12 inches from corners or the termination of bottom tracks (e.g., at door openings). Bolts shall extend a minimum of 15 inches into masonry or 7 inches into concrete.
   
b. All screw sizes shown are minimum.

TABLE R505.3.1(2)
FLOOR FASTENING SCHEDULEa

DESCRIPTION OF BUILDING ELEMENTS NUMBER AND SIZE OF FASTENERS SPACING OF FASTENERS
Floor joist to track of an interior load-bearing wall per Figures R505.3.1(7) and R505.3.1(8) 2 No. 8 screws Each joist
Floor joist to track at end of joist 2 No. 8 screws One per flange or two per bearing stiffener
Subfloor to floor joists No. 8 screws 6" o.c. on edges and 12" o.c. at intermediate supports

 

For SI: 1 inch = 25.4 mm.
   
a. All screw sizes shown are minimum.

 




 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm.

FIGURE R505.3.1(1)
FLOOR TO LOAD-BEARING WALL STUD CONNECTION

 




 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm.

FIGURE R505.3.1(2)
FLOOR TO WOOD SILL CONNECTION

 





For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm.

FIGURE R505.3.1(3)
FLOOR TO FOUNDATION CONNECTION

 




 FIGURE R505.3.1(4)FLOOR CANTILEVER TO LOAD-BEARING WALL CONNECTION

 




 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254.

FIGURE R505.3.1(5)
FLOOR CANTILEVER TO WOOD SILL CONNECTION

 




 

For SI: 1 inch = 25.4 mm, 1 mil = 0.0254

FIGURE R505.3.1(6)
FLOOR CANTILEVER TO FOUNDATION CONNECTION

 




 FIGURE R505.3.1(7)CONTINUOUS JOIST SPAN SUPPORTED ON STUD

 




 FIGURE R505.3.1(8)LAPPED JOISTS SUPPORTED ON STUD
505.3.2 Allowable joist spans. The clear span of cold- formed steel floor joists shall not exceed the limits set forth in Tables R505.3.2(1), R505.3.2(2), and R505.3.2(3). Floor joists shall have a minimum bearing length of 1.5 inches (38 mm). When continuous joists are used, the interior bearing supports shall be located within 2 feet (610 mm) of mid span of the steel joists, and the individual spans shall not exceed the span in Tables R505.3.2(2) and R505.3.2(3). Bearing stiffeners shall be installed at each bearing location in accordance with Section R505.3.4 and as shown in Figure R505.3.

Blocking is not required for continuous back-to-back floor joists at bearing supports. Blocking shall be installed between the joists for single continuous floor joists across bearing supports. Blocking shall be spaced at a maximum of 12 feet (3660 mm) on center. Blocking shall consist of C-shape or track section with a minimum thickness of 33 mils (0.84 mm). Blocking shall be fastened to each adjacent joist through a 33-mil (0.84 mm) clip angle, bent web of blocking or flanges of web stiffeners with two No. 8 screws on each side. The minimum depth of the blocking shall be equal to the depth of the joist minus 2 inches (51 mm). The minimum length of the angle shall be equal to the depth of the joist minus 2 inches (51 mm).

TABLE R505.3.2(1)
ALLOWABLE SPANS FOR COLD-FORMED STEEL JOISTS—SINGLE SPANS a, b 33 ksi STEEL

JOIST DESIGNATION 30 PSF LIVE LOAD 40 PSF LIVE LOAD
Spacing (inches) Spacing (inches)
12 16 19.2 24 12 16 19.2 24
550S162-33 11´ - 7" 10´- 7" 9´- 6" 8´- 6" 10´- 7" 9´- 3" 8´- 6" 7´- 6"
550S162-43 12´ - 8" 11´- 6" 10´ - 10" 10´- 2" 11´- 6" 10´- 5" 9´- 10" 9´- 1"
550S162-54 13´ - 7" 12´- 4" 11´- 7" 10´- 9" 12´- 4" 11´- 2" 10´- 6" 9´- 9"
550S162-68 14´ - 7" 13´- 3" 12´- 6" 11´- 7" 13´- 3" 12´- 0" 11´- 4" 10´- 6"
800S162-97 16´ - 2" 14´- 9" 13´- 10" 12´- 10" 14´- 9" 13´- 4" 12´- 7" 11´- 8"
800S162-33 15´- 8" 13´- 11" 12´- 9" 11´- 5" 14´- 3" 12´- 5" 11´- 3" 9´- 0"
800S162-43 17´- 1" 15´ - 6" 14´- 7" 13´- 7" 15´- 6" 14´- 1" 13´- 3" 12´- 4"
800S162-54 18´- 4" 16´- 8" 15´- 8" 14´- 7" 16´- 8" 15´- 2" 14´- 3" 13´- 3"
800S162-68 19´- 9" 17´- 11" 16´- 10" 15´- 8" 17´- 11" 16´- 3" 15´- 4" 14´- 2"
800S162-97 22´- 0" 20´- 0" 16´- 10" 17´- 5" 20´- 0" 18´- 2" 17´- 1" 15´- 10"
1000S162-43 20´- 6" 18´- 8" 17´- 6" 15´- 8" 18´- 8" 16´- 11" 15´- 6" 13´- 11"
1000S162-54 22´- 1" 20´- 0" 18´- 10" 17´- 6" 20´- 0" 18´- 2" 17´- 2" 15´- 11"
1000S162-68 23´- 9" 21´- 7" 20´- 3" 18´- 10" 21´- 7" 19´- 7" 18´- 5" 17´- 1"
1000S162-97 26´- 6" 24´- 1" 22´- 8" 21´- 0" 24´- 1" 21´- 10" 20´- 7" 19´- 1"
1200S162-43 23´- 9" 20´- 10" 19´- 0" 16´- 8" 21´- 5" 18´- 6" 16´- 6" 13´- 2"
1200S162-54 25´- 9" 23´- 4" 22´- 0" 20´- 1" 23´- 4" 21´- 3" 20´- 0" 17´- 10"
1200S162-68 27´- 8" 25´- 1" 23´- 8" 21´- 11" 25´- 1" 22´- 10" 21´- 6" 21´- 1"
1200S162-97 30´- 11" 28´- 1" 26´- 5" 24´ - 6" 28´- 1" 25´- 6" 24´- 0" 22´- 3"

 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Deflection criteria: L/480 for live loads, L/240 for total loads.
   
b. Floor dead load = 10 psf.

TABLE R505.3.2(2)
ALLOWABLE SPANS FOR COLD-FORMED STEEL JOISTS—MULTIPLE SPANSa, b 33 ksi STEEL

JOIST DESIGNATION  30 PSF LIVE LOAD  40 PSF LIVE LOAD
 Spacing (inches)  Spacing (inches)
12 16 19.2 24 12 16 19.2 24
550S162-33 12´- 1" 10´- 5" 9´- 6" 8´-6" 10´- 9" 9´- 3" 8´- 6" 7´- 6"
550S162-43 14´- 5" 12´- 5" 11´- 4" 10´- 2" 12´- 9" 11´- 11" 10´- 1" 9´- 0"
550S162-54 16´- 3" 14´- 1" 12´- 10" 11´- 6" 14´- 5" 12´- 6" 11´- 5" 10´- 2"
550S162-68 19´- 7" 17´- 9" 16´- 9" 15´- 6" 17´- 9" 16´- 2" 15´- 2" 14´- 1"
800S162-97 21´- 9" 19´- 9" 18´- 7" 17´- 3" 19´- 9" 17´- 11" 16´- 10" 15´- 4"
800S162-33 14´- 8" 11´- 10" 10´- 4" 8´- 8" 12´- 4" 9´- 11" 8´- 7" 7´- 2"
800S162-43 20´- 0" 17´- 4" 15´- 9" 14´- 1" 17´- 9" 15´- 4" 14´- 0" 12´- 0"
800S162-54 23´- 7" 20´- 5" 18´- 8" 16´- 8" 21´- 0" 18´- 2" 16´- 7" 14´- 10"
800S162-68 26´- 5" 23´- 1" 21´- 0" 18´- 10" 23´- 8" 20´- 6" 18´- 8" 16´- 9"
800S162-97 29´- 6" 26´- 10" 25´- 3" 22´- 8" 26´- 10" 24´- 4" 22´- 6" 20´- 2"
1000S162-43 22´- 2" 18´- 3" 16´- 0" 13´- 7" 18´- 11" 15´- 5" 13´- 6" 11´- 5"
1000S162-54 26´- 2" 22´- 8" 20´- 8" 18´- 6" 23´- 3" 20´- 2" 18´- 5" 16´- 5"
1000S162-68 31´- 5" 27´- 2" 24´- 10" 22´- 2" 27´- 11" 24´- 2" 22´- 1" 19´- 9"
1000S162-97 35´- 6" 32´- 3" 29´- 11" 26´- 9" 32´- 3" 29´- 2" 26´- 7" 23´- 9"
1200S162-43 21´- 8" 17´- 6" 15´- 3" 12´- 10" 18´- 3" 14´- 8" 12´- 8" 10´- 6"
1200S162-54 28´- 5" 24´- 8" 22´- 6" 19´- 6" 25´- 3" 21´- 11" 19´- 4" 16´- 6"
1200S162-68 33´- 7" 29´- 1" 26´- 6" 23´- 9" 29´- 10" 25´- 10" 23´- 7" 21´- 1"
1200S162-97 41´- 5" 37´- 8" 34´- 6" 30´- 10" 37´- 8" 33´- 6" 30´- 7" 27´- 5"


For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Deflection criteria: L/480 for live loads, L/240 for total loads.
   
b. Floor dead load = 10 psf.

TABLE R505.3.2(3)
ALLOWABLE SPANS FOR COLD-FORMED STEEL JOISTS—MULTIPLE SPANSa, b 50 ksi STEEL

JOIST DESIGNATION  30 PSF LIVE LOAD 40 PSF LIVE LOAD
 Spacing (inches) Spacing (inches)
12 16 19.2 24 12 16 19.2 24
550S162-33 13´- 11" 12´- 0" 11´- 0" 9´- 3" 12´- 3" 10´- 8" 9´- 7" 8´- 4"
550S162-43 16´- 3" 14´- 1" 12´- 10" 11´- 6" 14´- 6" 12´- 6" 11´- 5" 10´- 3"
550S162-54 18´- 2" 16´- 6" 15´- 4" 13´- 8" 16´- 6" 14´- 11" 13´- 7" 12´- 2"
550S162-68 19´- 6" 17´- 9" 16´- 8" 15´- 6" 17´- 9" 16´- 1" 15´- 2" 14´- 0"
550S162-97 21´- 9" 19´- 9" 18´- 6" 17´- 2" 19´- 8" 17´- 10" 16´- 8" 15´- 8"
800S162-33 15´- 6" 12´- 6" 10´- 10" 9´- 1" 13´- 0" 10´- 5" 8´- 11" 6´- 9"
800S162-43 22´- 0" 19´- 1" 17´- 5" 15´- 0" 19´- 7" 16´- 11" 14´- 10" 12´- 8"
800S162-54 24´- 6" 22´- 4" 20´- 6" 17´- 11" 22´- 5" 19´- 9" 17´- 11" 15´- 10"
800S162-68 26´- 6" 24´- 1" 22´- 8" 21´- 0" 24´- 1" 21´- 10" 20´- 7" 19´- 2"
800S162-97 29´- 9" 26´- 8" 25´- 2" 23´- 5" 26´- 8" 24´- 3" 22´- 11" 21´- 4"
1000S162-43 23´- 6" 19´- 2" 16´- 9" 14´- 2" 19´- 11" 16´- 2" 14´- 0" 11´- 9"
1000S162-54 28´- 2" 23´- 10" 21´- 7" 18´- 11" 24´- 8" 20´- 11" 18´- 9" 18´- 4"
1000S162-68 31´- 10" 28´- 11" 27´- 2" 25´- 3" 28´- 11" 26´- 3" 24´- 9" 22´- 9"
1000S162-97 35´- 4" 32´- 1" 30´- 3" 28´- 1" 32´- 1" 29´- 2" 27´- 6" 25´- 6"
1200S162-43 22´- 11" 18´- 5" 16´- 0" 13´- 4" 19´- 2" 15´- 4" 13´- 2" 10´- 6"
1200S162-54 32´- 8" 28´- 1" 24´- 9" 21´- 2" 29´- 0" 23´- 10" 20´- 11" 17’- 9"
1200S162-68 37´- 1" 32´- 5" 29´- 4" 25´- 10" 33´- 4" 28´- 6" 25´- 9" 22´- 7"
1200S162-97 41´- 2" 37´- 6" 35´- 3" 32´- 9" 37´- 6" 34´- 1" 32´- 1" 29´- 9"

 

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
   
a. Deflection criteria: L/480 for live loads, L/240 for total loads.
   
b. Floor dead load = 10 psf.
R505.3.3 Joist bracing. The top flanges of steel joists shall be laterally braced by the application of floor sheathing fastened to the joists in accordance with Table R505.3. 1(2). Floor joists with spans that exceed 12 feet (3658 mm) shall have the bottom flanges laterally braced in accordance with one of the following:
1. Gypsum board installed with minimum No. 6 screws in accordance with Section R702.
2. Continuous steel strapping installed in accordance with Figure R505.3. Steel straps shall be at least 1.5 inches (38 mm) in width and 33 mils (0.84 mm) in thickness. Straps shall be fastened to the bottom flange at each joist with at least one No. 8 screw and shall be fastened to blocking with at least two No. 8 screws. Blocking or bridging (X-bracing) shall be installed between joists in-line with straps at a maximum spacing of 12 feet (3658 mm) measured perpendicular to the joist run and at the termination of all straps.
R505.3.4 Bearing stiffeners. Bearing stiffeners shall be installed at all bearing locations for steel floor joists. A bearing stiffener shall be fabricated from a minimum 33 mil (0.84 mm) C-section or 43 mil (1.09 mm) track section. Each stiffener shall be fastened to the web of the joist with a minimum of four No. 8 screws equally spaced as shown in Figure R505.3.4. Stiffeners shall extend across the full depth of the web and shall be installed on either side of the web.

 




 FIGURE R505.3.4BEARING STIFFENER
R505.3.5 Cutting and notching. Flanges and lips of load-bearing steel floor framing members shall not be cut or notched.
R505.3.6 Hole patching. Web holes not conforming to the requirements in Section R505.2 shall be designed in accordance with one of the following:

Framing members shall be replaced or designed in accordance with accepted engineering practices when web holes exceed the following size limits:

1.1. The depth of the hole, measured across the web, exceeds 70 percent of the flat width of the web; or

1.2. The length of the hole measured along the web, exceeds 10 inches (254 mm) or the depth of the web, whichever is greater.
2. Web holes not exceeding the dimensional requirements in Section R505.3.6, Item 1, shall be patched with a solid steel plate, stud section, or track section in accordance with Figure R505.3.6. The steel patch shall, as a minimum, be of the same thickness as the receiving member and shall extend at least 1 inch (25 mm) beyond all edges of the hole. The steel patch shall be fastened to the web of the receiving member with No.8 screws spaced no greater than 1 inch (25 mm) center-to-center along the edges of the patch with minimum edge distance of 1/2 inch (13 mm).
R505.3.7 Floor cantilevers. Floor cantilevers shall not exceed 24 inches (610 mm) as illustrated in Figure R505.3. The cantilever back-span shall extend a minimum of 6 feet (1830 mm) within the building, and shall be fastened to a bearing condition in accordance with Section R505.3.1. Floor cantilevers shall be permitted only on the second floor of a two-story building or the first floor of a one-story building. Floor framing that is cantilevered and supports the cantilevered floor only shall consist of single joist members in accordance with Section R505.3.2. Floor framing that is cantilevered and supports the cantilevered floor and the roof framing load above shall consist of double joist members of the same size and material thickness as that for single joist members in accordance with Section R505.3.2, and shall be fastened web-to-web with minimum No. 8 screws at 24 inches (610 mm) maximum on-center spacing top and bottom. Built-up floor framing consisting of a C-section inside a track section, fastened at the top and bottom flanges by minimum No. 8 screws at 24 inches (610 mm) maximum on center spacing, is permitted in lieu of the web-to-web double joist method.
R505.3.8 Splicing. Joists and other structural members shall not be spliced. Splicing of tracks shall conform with Figure R505.3.8.
R505.3.9 Framing of openings. Openings in floor framing shall be framed with header and trimmer joists. Header joist spans shall not exceed 8 feet (2438 mm). Header and trimmer joists shall be fabricated from joist and track sections, which shall be of a minimum size and thickness as the adjacent floor joists and shall be installed in accordance with Figure R505.3. Each header joist shall be connected to trimmer joists with a minimum of four 2-inch-by-2-inch (51 mm by 51 mm) clip angles. Each clip angle shall be fastened to both the header and trimmer joists with four No. 8 screws, evenly spaced, through each leg of the clip angle. The clip angles shall have a steel thickness not less than that of the floor joist.

 




 

For SI: 1 inch = 25.4 mm.

FIGURE R505.3.6
HOLE PATCH

 




 

For SI: 1 inch = 25.4 mm.

FIGURE R505.3.8
TRACK SPLICE
Concrete slab-on-ground floors shall be a minimum 3.5 inches (89 mm) thick (for expansive soils, see Section R403.1.8). The specified compressive strength of concrete shall be as set forth in Section R402.2.
The area within the foundation walls shall have all vegetation, top soil and foreign material removed.
Fill material shall be free of vegetation and foreign material. The fill shall be compacted to assure uniform support of the slab, and except where approved by a registered design professional, the fill depths shall not exceed 24 inches (610 mm) for clean sand or gravel and 8 inches (203 mm) for earth.
A 4-inch-thick (102 mm) base course consisting of clean graded sand, gravel, crushed stone or crushed blast-furnace slag passing a 2-inch (51 mm) sieve shall be placed on the prepared subgrade when the slab is below grade.

Exception:
A base course is not required when the concrete slab is installed on well-drained or sand-gravel mixture soils classified as Group I according to the United Soil Classification System in accordance with Table R405.1.
A 6 mil (0.006 inch; 152 µm) polyethylene or approved vapor retarder with joints lapped not less than 6 inches (152 mm) shall be placed between the concrete floor slab and the base course or the prepared subgrade where no base course exists.

Exception:
The vapor retarder may be omitted:
1. From garages, utility buildings and other unheated accessory structures.
2. From driveways, walks, patios and other flatwork not likely to be enclosed and heated at a later date.
3. Where approved by the building official, based on local site conditions.
Where provided in slabs on ground, reinforcement shall be supported to remain in place from the center to upper one third of the slab for the duration of the concrete placement.
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