CODE CHANGE PROPOSAL FORM (See instructions on page 2) Proponent: Charles S. Bajnai, Chesterfield County, VA, ICC Building Code Action Committee

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1 CODE CHANGE PROPOSAL FORM (See instructions on page 2) Code: IRC 12/13 Tables R Proponent: Charles S. Bajnai, Chesterfield County, VA, ICC Building Code Action Committee Revise as follows: 1. Revise Table R as follows: TABLE R WINDBORNE DEBRIS PROTECTION FASTENING SCHEDULE FOR WOOD STRUCTURAL PANELS Footnote a. This table is based on a 130mph basic wind speeds and a 33-foot mean roof height. 2. Revise Section R as follows: R Applicability limits. The provisions of this section shall control the construction of cold-formed steel floor framing for buildings not greater than 60 feet ( mm) in length perpendicular to the joist span, not greater than 40 feet ( mm) in width parallel to the joist span, and less than or equal to three stories above grade plane. Cold-formed steel floor framing constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum where the basic design wind speed is not greater than of 110 miles per hour (49 m/s), the Exposure Category is B or C, and the a maximum ground snow load is not greater than of 70 pounds per square foot (3.35 kpa). 3. Revise Table as follows: TABLE R MAXIMUM ALLOWABLE LENGTH OF WOOD WALL STUDS EXPOSED TO WIND SPEEDS OF 100 mph OR LESS IN SEISMIC DESIGN CATEGORIES A, B, C, D0, D1 and D2 a. Design required. b. Table is limited to buildings located where the basic wind speed is 100mph or less and for which the seismic design category is A, B, C, D0, D1, or D2 cb. Applicability of this table assumes the following: Snow load not exceeding 25 psf, fb not less than 1310 psi determined by multiplying the AF&PA NDS tabular base design value by the repetitive use factor, and by the size factor for all species except southern pine, E not less than psi, tributary dimensions for floors and roofs not exceeding 6 feet, maximum span for floors and roof not exceeding 12 feet, eaves not over 2 feet in dimension and exterior sheathing. Where the conditions are not within these parameters, design is required. dc. Utility, standard, stud and No. 3 grade lumber of any species are not permitted.

2 4. Revise Table as follows: TABLE R602.3(2) ALTERNATE ATTACHMENTS TO TABLE R602.3(1) Footnote g. Specified alternate attachments for roof sheathing shall be permitted for basic wind speeds less than 100 mph. Fasteners attaching wood structural panel roof sheathing to gable end wall framing shall be installed using the spacing listed for panel edges. 5. Revise Table as follows: TABLE R602.3(3) REQUIREMENTS FOR WOOD STRUCTURAL PANEL WALL SHEATHING USED TO RESIST WIND a, b, c PRESSURES MINIMUM NAIL Size Penetration (inches) MINIMUM WOOD STRUCTURAL PANEL SPAN RATING MINIMUM NOMINAL PANEL THICKNESS (inches) MAXIMUM WALL STUD SPACING (inches) PANEL NAIL SPACING Edges (inches o.c.) Field (inches o.c.) MAXIMUM BASIC WIND SPEED (mph) Wind exposure category B C D 6. Revise Table R as follows: TABLE R BRACED WALL LINE SPACING APPLICATION CONDITION BUILDING TYPE Wind bracing Basic wind speed 85mph to 110 mph BRACED WALL LINE SPACING CRITERIA Exception to Maximum Spacing Maximum Spacing Detached, Townhouse 60 feet None 7. Revise Table as follows: TABLE R (1) BRACING REQUIREMENTS BASED ON WIND SPEED Footnote c. Method CS-SFB does not apply where the basic wind speed is greater than 100 mph.

3 8. Revise Table as follows: TABLE R BRACING METHODS Footnote d. Method CS-SFB does not apply in Seismic Design Categories D0, D1 and D2 and in areas where the basic wind speed exceeds 100 mph. 9. Revise Table as follows: METHOD (See Table R ) ABW SDC A, B and C basic wind speed < 110 mph SDC D o, D 1 and D 2, basic wind speed < 110 mph TABLE R MINIMUM LENGTH OF BRACED WALL PANELS MINIMUM LENGTH a (in) Wall Height 8 feet 9 feet 10 feet 11 feet 12 feet NP NP CONTRIBUTING LENGTH (in) Revise Table as follows: TABLE R MINIMUM HOLD-DOWN FORCES FOR METHOD ABW BRACED WALL PANELS SEISMIC DESIGN CATEGORY AND WIND SPEED SDC A, B and C Basic w Wind speed < 110 mph SDC D o, D 1 and D 2 Basic w Wind speed < 110 mph SUPPORTING/STORY HOLD DOWN FORCE (lb) Height of Braced Wall Panel 8 ft 9 ft 10 ft 11 ft 12 ft One story First of two story One story NP a NP a First of two story NP a NP a 11. Revise Section R as follows: R Length of bracing. The length of bracing along each braced wall line shall be the greater of that required by the basic design wind speed and braced wall line spacing in accordance with Table R (1) as adjusted by the factors in the Table R (2) or the Seismic Design Category and braced wall line length in accordance with Table R Angled walls shall be permitted to be counted in accordance with Section R , and braced wall panel location shall be in accordance

4 with Section R The seismic adjustment factors in Table R (4) shall not be applied to the length of bracing determined using Table R In no case shall the minimum total length of bracing in a braced wall line, after all adjustments have been taken, be less than 48 inches (1219 mm) total. 12. Revise Section R as follows: R Connections to roof framing. Top plates of exterior braced wall panels shall be attached to rafters or roof trusses above in accordance with Table R602.3(1) and this section. Where required by this section, blocking between rafters or roof trusses shall be attached to top plates of braced wall panels and to rafters and roof trusses in accordance with Table R602.3(1). A continuous band, rim, or header joist or roof truss parallel to the braced wall panels shall be permitted to replace the blocking required by this section. Blocking shall not be required over openings in continuously-sheathed braced wall lines. In addition to the requirements of this section, lateral support shall be provided for rafters and ceiling joists in accordance with Section R802.8 and for trusses in accordance with Section R Roof ventilation shall be provided in accordance with Section R For Seismic Design Categories A, B and C and basic wind speeds less than 100 mph (45 m/s) where the distance from the top of the braced wall panel to the top of the rafters or roof trusses above is 91/4 inches (235 mm) or less, blocking between rafters or roof trusses shall not be required. Where the distance from the top of the braced wall panel to the top of the rafters or roof trusses above is between 91/4 inches (235 mm) and 151/4 inches (387 mm), blocking between rafters or roof trusses shall be provided above the braced wall panel in accordance with Figure R (1). 2. For Seismic Design Categories D0, D1 and D2 or basic wind speeds of 100 mph (45 m/s) or greater, where the distance from the top of the braced wall panel to the top of the rafters or roof trusses is 151/4 inches (387 mm) or less, blocking between rafters or roof trusses shall be provided above the braced wall panel in accordance with Figure R (1). 2. (remains unchanged). 13. Revise Section R and corresponding table as follows: R Applicability limits. The provisions of this section shall control the construction of exterior coldformed steel wall framing and interior load-bearing cold-formed steel wall framing for buildings not more than 60 feet ( mm) long perpendicular to the joist or truss span, not more than 40 feet ( mm) wide parallel to the joist or truss span, and less than or equal to three stories above grade plane. All exterior walls installed in accordance with the provisions of this section shall be considered as loadbearing walls. Cold-formed steel walls constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum where the basic design wind speed is not greater than of 110 miles per hour (49 m/s), the Exposure Category is B or C, and the a maximum ground snow load is not greater than of 70 pounds per square foot (3.35 kpa). TABLE R WALL TO FOUNDATION OR FLOOR CONNECTION REQUIREMENTS a,b BASIC WIND SPEED (mph) AND EXPOSURE FRAMING CONDITION 85 B 90 B 85 C 100 B 90 C 110 B 100 C < 110 C

5 14. Revise Tables R (2) through R (31), and Tables R (1) through R (4) all the same way: BASIC WIND SPEED Exp. B TABLE R (2) a, b, c 24-FOOT-WIDE BUILDING SUPPORTING ROOF AND CEILING ONLY 33 ksi STEEL MINIMUM STUD THICKNESS (mils) STUD 8-Foot Studs 9-Foot Studs 10-Foot Studs MEMBER SPACING Ground Snow Load (psf) SIZE (inches) Exp. C (Make same change for Tables R (3) through R (31), and Tables R (1) through R (4)) 15. Revise Footnote b in Table R603.8 as follows:. TABLE R603.8 HEAD AND SILL TRACK SPAN Footnote b. Head and sill track spans are based on components and cladding wind pressures speeds and 48 inch tributary span. 16. Revise Section R as follows: R Where the basic wind speeds are in excess of exceeds 100 miles per hour (45 m/s) and, Exposure C or D applies, walls shall be provided with wind direct uplift connections in accordance with AISI S230, Section E13.3, and AISI S230, Section F7.2, as required for 110 miles per hour (49 m/s), Exposure C 17. Revise Section R611.2 as follows: R611.2 Applicability limits. The provisions of this section shall apply to the construction of exterior concrete walls for buildings not greater than 60 feet ( mm) in plan dimensions, floors with clear spans not greater than 32 feet (9754 mm) and roofs with clear spans not greater than 40 feet ( mm). Buildings shall not exceed 35 feet ( mm) in mean roof height or two stories in height abovegrade. Floor/ceiling dead loads shall not exceed 10 pounds per square foot (479 Pa), roof/ceiling dead loads shall not exceed 15 pounds per square foot (718 Pa) and attic live loads shall not exceed 20 pounds per square foot (958 Pa). Roof overhangs shall not exceed 2 feet (610 mm) of horizontal projection beyond the exterior wall and the dead load of the overhangs shall not exceed 8 pounds per square foot (383 Pa). Walls constructed in accordance with the provisions of this section shall be limited to buildings subjected to a maximum where the basic design wind speed is not greater than of 130 miles per hour (58 m/s) Exposure B, 110 miles per hour (49 m/s) Exposure C and 100 miles per hour (45 m/s) Exposure D. Walls constructed in accordance with the provisions of this section shall be limited to detached one- and twofamily dwellings and townhouses assigned to Seismic Design Category A or B, and detached one- and two-family dwellings assigned to Seismic Design Category C.

6 18 Revise Tables R611.6(1) through R611.6(4) all the same way: TABLE R611.6(1) MINIMUM VERTICAL REINFORCEMENT FOR FLAT ABOVE-GRADE WALLS (Make same change for Tables R611(2) through R611(4)) a, b, c, d, e BASIC MAXIMUM WIND SPEED (mph) MAXIMUM UNSUPPORTED WALL HEIGHT PER STORY (feet) 19. Revise Section R613.2 as follows: MINIMUM VERTICAL REINFORCEMENT BAR SIZE AND SPACING (inches) f, g Nominal h wall thickness (inches) Exposure Category B C D Top i Side i Top i Side i Top i Side i Top i Side i R613.2 Applicability limits. The provisions of this section shall control the construction of exterior structural insulated panel walls and interior load-bearing structural insulated panel walls for buildings not greater than 60 feet ( mm) in length perpendicular to the joist or truss span, not greater than 40 feet ( mm) in width parallel to the joist or truss span and not greater than two stories in height with each wall not greater than 10 feet (3048 mm) high. All exterior walls installed in accordance with the provisions of this section shall be considered as load-bearing walls. Structural insulated panel walls constructed in accordance with the provisions of this section shall be limited to sites where the basic subjected to a maximum design wind speed is not greater than of 130 miles per hour (58 m/s), the Exposure Category is A, B or C, and a maximum the ground snow load is not greater than of 70 pounds per foot (3.35 kpa), and the Seismic Design Category is Categories A, B, or and C. 20. Revise Tables R613.5(1) and R613.5(2) both the same way: TABLE R613.5(1) MINIMUM THICKNESS FOR SIP WALL SUPPORTING SIP LIGHT-FRAME ROOF ONLY (inches) BASIC WIND SPEED (3-second gust) (mph) Exp. A/B Exp. C SNOW LOAD (psf) MINIMUM STUD THICKNESS (mils) Wall Height (ft) Wall Height (ft) Wall Height (ft) Wall Height (ft) Wall Height (ft) Revise Section R as follows: R Applicability limits. The provisions of this section shall control the design of truss roof framing when snow controls for buildings not greater than 60 feet ( mm) in length perpendicular to the joist, rafter or truss span, not greater than 36 feet ( mm) in width parallel to the joist, rafter or truss span, not greater than two stories in height with each story not greater than 10 feet (3048 mm) high, and roof slopes not smaller than 3:12 (25-percent slope) or greater than 12:12 (100-percent slope). Truss roof framing constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum where the basic design wind speed is not greater than of 110 miles per hour (49 m/s), the Exposure Category is A, B or C, and the a maximum ground snow load is not greater than of 70 pounds per square foot (3.35 kpa). For consistent loading of all truss types, roof snow load is to be computed as: 0.7 pg.

7 22. Revise Section R as follows: R Applicability limits. The provisions of this section shall control the construction of cold-formed steel roof framing for buildings not greater than 60 feet ( mm) perpendicular to the joist, rafter or truss span, not greater than 40 feet ( mm)in width parallel to the joist span or truss, less than or equal to three stories above grade plane and with roof slopes not less than 3:12 (25-percent slope) or greater than 12:12 (100 percent slope). Cold-formed steel roof framing constructed in accordance with the provisions of this section shall be limited to sites subjected to a maximum where the basic design wind speed is not greater than of 110 miles per hour (49 m/s), the Exposure Category is B or C, and the a maximum ground snow load is not greater than of 70 pounds per square foot (3.35 kpa). 23. Revise Section R as follows: R Minimum roof rafter sizes. Roof rafter size and thickness shall be determined in accordance with the limits set forth in Tables R (1) and R (2) based on the horizontal projection of the roof rafter span. For determination of roof rafter sizes, reduction of roof spans shall be permitted when a roof rafter support brace is installed in accordance with Section R The reduced roof rafter span shall be taken as the larger of the distance from the roof rafter support brace to the ridge or to the heel measured horizontally. For the purpose of determining roof rafter sizes in Tables R (1) and R (2), basic wind speeds shall be converted to equivalent ground snow loads in accordance with Table R (3). Roof rafter sizes shall be based on the higher of the ground snow load or the equivalent snow load converted from the basic wind speed. 24. Revise Section R as follows: R Hip framing. Hip framing shall consist of jack-rafters, hip members, hip support columns and connections in accordance with this section, or shall be in accordance with an approved design. The provisions of this section for hip members and hip support columns shall apply only where the jack rafter slope is greater than or equal to the roof slope. For the purposes of determining member sizes in this section, basic wind speeds shall be converted to equivalent ground snow load in accordance with Table R (3). 25. Revise Section R as follows: R Application. Tile shall be applied in accordance with this chapter and the manufacturer's installation instructions, based on the following: Clay and concrete roof tiles shall be fastened in accordance with this section and the manufacturer s installation instructions. Perimeter tiles shall be fastened with a minimum of one fastener per tile. Tiles with installed weight less than 9 pounds per square foot (0.4 kg/m2) require a minimum of one fastener per tile regardless of roof slope. Clay and concrete roof tile attachment shall be in accordance with the manufacturer s installation instructions where applied in areas where the basic wind speed exceeds 100 miles per hour (45 m/s) and on buildings where the roof is located more than 40 feet ( mm) above grade. In areas subject to snow, a minimum of two fasteners per tile is required. In all other areas, clay and concrete roof tiles shall be attached in accordance with Table R Reason: This proposal is submitted by the ICC Building Code Action Committee (BCAC) The BCAC was established by the ICC Board of Directors to pursue opportunities to improve and enhance an assigned International Code or portion thereof. This includes both the technical aspects of the codes as well as the code content in terms of scope and application of referenced standards. Since its inception in July, 2011, the BCAC has held 6 open meetings and numerous workgroup calls which included members of the BCAC as well as any interested party to discuss and debate the proposed changes. Related documentation and reports are posted on the BCAC website at:

8 The purpose of this proposal is to coordinate terminology in the code. Figure R (A) supplies the basic wind speed, defined as the three-second gust speed at 33 feet ( mm) above the ground in Exposure C (see Section R ). This wind speed, derived from ASCE 7, is a design wind speed based on an extensive modeling process using historical data, wind characteristics and computer simulations. It is not necessarily the maximum wind speed that can be experienced by a site, nor does it suggest the maximum wind speed an element is capable of resisting due to factors of safety in material standards and design procedures. This proposal corrects references throughout the IRC to properly refer to basic wind speed. Cost Impact:????????????