Where a framing anchor is used to support the header in lieu of a jack stud in accordance with Note d of Table R Fireblocking shall be provided in accordance with Section R Buildings shall be braced in accordance with this section or, when applicable, Section R Where a building, or portion thereof, does not comply with one or more of the bracing requirements in this section, those portions shall be designed and constructed in accordance with Section R For the purpose of determining the amount and location of bracing required in each story level of a building, braced wall lines shall be designated as straight lines in the building plan placed in accordance with this section.
Exterior walls parallel to a braced wall line shall be offset not more than 4 feet mm from the designated braced wall line location as shown in Figure R Interior walls used as bracing shall be offset not more than 4 feet mm from a braced wall line through the interior of the building as shown in Figure R SDC D 0 , D 1 , D 2 Detached, townhouses , one- and two- story only 25 feet Up to 35 feet to allow for a single room not to exceed square feet.
Spacing of all other braced wall lines shall not exceed 25 feet. Braced wall panel s shall be full-height sections of wall that shall not have vertical or horizontal offsets. Braced wall panel s shall be constructed and placed along a braced wall line in accordance with this section and the bracing methods specified in Section R The bracing lengths in Table R The end of each braced wall panel closest to the end of the braced wall line shall have an 1, lb 8 kN hold-down device fastened to the stud at the edge of the braced wall panel closest to the corner and to the foundation or framing below as shown in End Condition 5 of Figure R Braced wall lines with a length of 16 feet mm or less shall have not less than two braced wall panel s of any length or one braced wall panel equal to 48 inches mm or more.
Braced wall lines greater than 16 feet mm shall have not less than two braced wall panel s. The required length of bracing along each braced wall line shall be determined as follows: All buildings in Seismic Design Categories A and B shall use Table R Linear interpolation shall be permitted. Method LIB shall have gypsum board fastened to not less than one side with nails or screws in accordance with Table R Spacing of fasteners at panel edges shall not exceed 8 inches.
Where three or more parallel braced wall lines are present and the distances between adjacent braced wall lines are different, the average dimension shall be permitted to be used for braced wall line spacing.
Section R The total adjustment factor is the product of all applicable adjustment factors. The adjustment factor is permitted to be 1. The same adjustment factor shall be applied to all braced wall lines on all floors of the structure, based on the worst-case exposure category. Wall bracing lengths are based on a soil site class "D.
Where the braced wall line length is greater than 50 feet, braced wall lines shall be permitted to be divided into shorter segments having lengths of 50 feet or less, and the amount of bracing within each segment shall be in accordance with this table. Where more than one bracing method is used, mixing methods shall be in accordance with Section R Interior gypsum board. The total length of bracing required for a given wall line is the product of all applicable adjustment factors.
Applies to stone or masonry veneer exceeding the first story height. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpendicular to and laterally supporting veneered walls. See Section R Table R Gypsum board.
Applies to panels next to garage door opening where supporting gable end wall or roof load only. Shall only be used on one wall of the garage. A full-height clear opening shall not be permitted adjacent to a Method CS-G panel. Method applies to detached one- and two-family dwellings in Seismic Design Categories D 0 through D 2 only.
Mixing of bracing methods shall be permitted as follows: Mixing intermittent bracing and continuous sheathing methods from story to story shall be permitted. Mixing intermittent bracing methods from braced wall line to braced wall line within a story shall be permitted. Mixing intermittent bracing methods along a braced wall line shall be permitted in Seismic Design Categories A and B, and detached dwellings in Seismic Design Category C, provided that the length of required bracing in accordance with Table R Intermittent methods ABW, PFH and PFG shall be permitted to be used along a braced wall line with continuous sheathed methods, provided that the length of required bracing for that braced wall line is determined in accordance with Table R The length of required bracing shall be the highest value of all intermittent bracing methods used in accordance with Table R The requirements of Section R Continuous sheathing methods require structural panel sheathing to be used on all sheathable surfaces on one side of a braced wall line including areas above and below openings and gable end walls and shall meet the requirements of Section R An approved interior finish material with an in-plane shear resistance equivalent to gypsum board shall be permitted to be substituted, unless otherwise required by Section R Except for Method LIB, gypsum wall board is permitted to be omitted provided that the required length of bracing in Tables R Vertical joints of panel sheathing shall be permitted to occur over double studs, where adjoining panel edges are attached to separate studs with the required panel edge fastening schedule, and the adjacent studs are attached together with two rows of 10d box nails [3 inches by 0.
Blocking at horizontal joints shall not be required in wall segments that are not counted as braced wall panels. Where Method GB panels are installed horizontally, blocking of horizontal joints is not required. Use the actual length where it is greater than or equal to the minimum length. For purposes of computing the required length of bracing in Tables R Straps shall be installed in accordance with manufacturer's recommendations.
The total area of the veneer on the second- story exterior walls shall be permitted to extend up to 25 percent of the occupied second floor area. The veneer on the second- story exterior walls shall be permitted to cover one side of the dwelling , including walls on bay windows and similar appurtenances within the one dwelling side. Hold-down force is minimum allowable stress design load for connector providing uplift tie from wall framing at end of braced wall panel at the noted story to wall framing at end of braced wall panel at the story below, or to foundation or foundation wall.
Use single- story hold-down force where edges of braced wall panels do not align; a continuous load path to the foundation shall be maintained. Where hold-down connectors from stories above align with stories below, use cumulative hold-down force to size middle- and bottom- story hold-down connectors.
The length of bracing along each braced wall line shall be the greater of that required by the ultimate design wind speed and braced wall line spacing in accordance with Table R Angled walls shall be permitted to be counted in accordance with Section R Spacing between braced wall lines shall be in accordance with Table R The seismic adjustment factors in Table R The minimum total length of bracing in a braced wall line , after all adjustments have been taken, shall be not less than 48 inches mm total.
Braced wall panel s shall be connected to floor framing or foundations as follows: Where joists are perpendicular to a braced wall panel above or below, a rim joist, band joist or blocking shall be provided along the entire length of the braced wall panel in accordance with Figure R Fastening of top and bottom wall plates to framing, rim joist, band joist or blocking shall be in accordance with Table R Where joists are parallel to a braced wall panel above or below, a rim joist, end joist or other parallel framing member shall be provided directly above and below the braced wall panel in accordance with Figure R Where a parallel framing member cannot be located directly above and below the panel, full-depth blocking at inch mm spacing shall be provided between the parallel framing members to each side of the braced wall panel in accordance with Figure R Fastening of blocking and wall plates shall be in accordance with Table R Connections of braced wall panel s to concrete or masonry shall be in accordance with Section R Braced wall panel s shall be fastened to required foundations in accordance with Section R Soffit blocking panels constructed in accordance with Figure R Vertical blocking panels constructed in accordance with Figure R Blocking panels provided by the roof truss manufacturer and designed in accordance with Section R Blocking, blocking panels or other methods of lateral load transfer designed in accordance with the AWC WFCM or accepted engineering practice.
Methods of bracing shall be as described in Section R Braced wall panel support shall be provided as follows: Cantilevered floor joists complying with Section R Raised floor system post or pier foundations supporting braced wall panel s shall be designed in accordance with accepted engineering practice.
Masonry stem walls with a length of 48 inches mm or less supporting braced wall panel s shall be reinforced in accordance with Figure R Masonry stem walls with a length greater than 48 inches mm supporting braced wall panel s shall be constructed in accordance with Section R Concrete stem walls with a length of 48 inches mm or less, greater than 12 inches mm tall and less than 6 inches mm thick shall have reinforcement sized and located in accordance with Figure R Cripple walls shall be constructed in accordance with Section R Cripple walls shall be braced with the length and method of bracing used for the wall above in accordance with Tables R Where gypsum wall board is not used on the inside of the cripple wall bracing, the length adjustments for the elimination of the gypsum wallboard, or equivalent, shall be applied as directed in Tables R This adjustment shall be taken in addition to the 1.
Where all cripple wall segments along a braced wall line do not exceed 48 inches mm in height, the cripple walls shall be permitted to be redesignated as a first- story wall for purposes of determining wall bracing requirements.
Where any cripple wall segment in a braced wall line exceeds 48 inches mm in height, the entire cripple wall shall be counted as an additional story. If the cripple walls are redesignated, the stories above the redesignated story shall be counted as the second and third stories , respectively. Braced wall line sills shall be anchored to concrete or masonry foundations in accordance with Sections R Plate washers, not less than 0.
In all buildings located in Seismic Design Categories D 0 , D 1 or D 2 , where the height of a required braced wall line that extends from foundation to floor above varies more than 4 feet mm , the braced wall line shall be constructed in accordance with the following: Where the lowest floor framing rests directly on a sill bolted to a foundation not less than 8 feet mm in length along a line of bracing, the line shall be considered as braced.
The double plate of the cripple stud wall beyond the segment of footing that extends to the lowest framed floor shall be spliced by extending the upper top plate not less than 4 feet mm along the foundation.
Anchor bolts shall be located not more than 1 foot and 3 feet and mm from the step in the foundation. Where cripple walls occur between the top of the foundation and the lowest floor framing, the bracing requirements of Sections R Where only the bottom of the foundation is stepped and the lowest floor framing rests directly on a sill bolted to the foundations, the requirements of Sections R There shall be not more than three stories above the top of a concrete or masonry foundation or basement wall.
Permanent wood foundations shall not be permitted. Floors shall not cantilever more than 24 inches mm beyond the foundation or bearing wall below. Wall height shall not be greater than 10 feet mm. The building shall have a roof eave-to- ridge height of 15 feet mm or less. Cripple walls shall not be permitted in three- story buildings. Where all framed portions of all exterior walls are sheathed in accordance with Section R Where the exterior walls are braced with sheathing panels in accordance with Section R Segments of wall compliant with Section R The number of bracing units shall be determined by dividing the wall segment length by the minimum bracing unit length.
Full-height sheathed segments of wall narrower than the minimum bracing unit length shall not contribute toward a bracing unit except as specified in Section R Interpolation shall not be permitted. Cripple walls or wood-framed basement walls in a walk-out condition shall be designated as the first story and the stories above shall be redesignated as the second and third stories , respectively, and shall be prohibited in a three- story structure.
Actual lengths of the sides of the circumscribed rectangle shall be rounded to the next highest unit of 10 when using this table. For Exposure Category C, multiply bracing units by a factor of 1.
A bracing unit shall begin not more than 12 feet mm from any wall corner. The distance between adjacent edges of bracing units shall be not greater than 20 feet mm. Segments of wall greater than 8 feet mm in length shall have not less than one bracing unit. The bracing methods referenced in Section R Each CS-G panel shall be equivalent to 0. Each CS-PF panel shall equal 0. Not more than four CS-PF panels shall be permitted on all segments of walls parallel to each side of the circumscribed rectangle.
Braced wall panels constructed as Method ABW, PFH and PFG shall be permitted where bracing units are constructed using wood structural panels applied either continuously or intermittently. For bracing units located along the eaves, the vertical distance from the outside edge of the top wall plate to the roof sheathing above shall not exceed 9.
Concrete stem walls with a length of 48 inches mm or less, greater than 12 inches mm tall and less than 6 inches mm thick shall be reinforced sized and located in accordance with Figure R Elements shall be straight and free of any defects that would significantly affect structural performance.
Cold-formed steel wall framing members shall be in accordance with the requirements of this section. The provisions of this section shall control the construction of exterior cold-formed steel wall framing and interior load-bearing cold-formed steel wall framing for buildings not more than 60 feet 18 mm long perpendicular to the joist or truss span, not more than 40 feet 12 mm wide parallel to the joist or truss span, and less than or equal to three stories above grade plane.
Exterior walls installed in accordance with the provisions of this section shall be considered as load-bearing walls. Load-bearing cold-formed steel wall framing members shall be in accordance with this section. Load-bearing cold-formed steel framing members shall be cold formed to shape from structural-quality sheet steel complying with the requirements of ASTM A Structural Grades 33 Type H and 50 Type H.
The member designation is defined by the first number representing the member depth in hundredths of an inch, "S" representing a stud or joist member, the second number representing the flange width in hundredths of an inch, and the letter "t" shall be a number representing the minimum base metal thickness in mils.
Load-bearing cold-formed steel framing members shall have a legible label , stencil, stamp or embossment with the following information as a minimum: Manufacturer's identification.
Minimum base steel thickness in inches mm. Minimum coating designation. Minimum yield strength, in kips per square inch ksi MPa. Structural sheathing shall be attached to cold-formed steel studs with minimum No. Screws for attaching structural sheathing to cold-formed steel wall framing shall have a minimum head diameter of 0.
Gypsum board shall be attached to cold-formed steel wall framing with minimum No. For connections, screws shall extend through the steel not fewer than three exposed threads. Fasteners shall have rust-inhibitive coating suitable for the installation in which they are being used, or be manufactured from material not susceptible to corrosion.
Web holes, web hole reinforcing and web hole patching shall be in accordance with this section. Web holes in wall studs and other structural members shall comply with all of the following conditions: Holes shall conform to Figure R Holes shall be permitted only along the centerline of the web of the framing member.
Holes shall have a center-to-center spacing of not less than 24 inches mm. Holes shall have a web hole width not greater than 0. 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 mm.
Web holes in gable endwall studs not conforming to the requirements of Section R The reinforcing shall be a steel plate or C-shaped section with a hole that does not exceed the web hole size limitations of Section R The steel reinforcing shall be the same thickness as the receiving member and shall extend not less than 1 inch 25 mm beyond all edges of the hole.
The steel reinforcing shall be fastened to the web of the receiving member with No. The depth of the hole, measured across the web, exceeds 70 percent of the flat width of the web. The length of the hole measured along the web exceeds 10 inches mm or the depth of the web, whichever is greater.
Web holes not exceeding the dimensional requirements in Section R The steel patch shall, as a minimum, be the same thickness as the receiving member and shall extend not less than 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.
Exterior cold-formed steel framed walls and interior load-bearing cold-formed steel framed walls shall be constructed in accordance with the provisions of this section. Anchor bolts are to be located not more than 12 inches from corners or the termination of bottom tracks, such as at door openings or corners.
Bolts are to extend not less than 15 inches into masonry or 7 inches into concrete. All screw sizes shown are minimum. Foundation anchor straps are permitted in place of anchor bolts, if spaced as required to provide equivalent anchorage to the required anchor bolts and installed in accordance with manufacturer's requirements. Refer to Table R Where attachment is not given, special design is required. Stud height, h , is measured from wall bottom track to wall top track or brace connection height.
Foundation anchor straps are permitted in place of anchor bolts if spaced as required to provide equivalent anchorage to the required anchor bolts and installed in accordance with manufacturer's requirements. Screws for attachment of structural sheathing panels are to be bugle-head, flat-head, or similar head styles with a minimum head diameter of 0. Design load assumptions: Second-floor dead load is 10 psf. Second-floor live load is 30 psf.
Blocking between ceiling joists or rafters to top plate. Ceiling joist not attached to parallel rafter, laps over partitions see Section R Ceiling joist attached to parallel rafter heel joint see Section R Roof rafters to ridge, valley or hip rafters or roof rafter to minimum 2" ridge beam.
Stud to stud not at braced wall panels. Stud to stud and abutting studs at intersecting wall corners at braced wall panels. Face nail on each side of end joint minimum 24" lap splice length each side of end joint. Bottom plate to joist, rim joist, band joist or blocking not at braced wall panels.
Bottom plate to joist, rim joist, band joist or blocking at braced wall panel. Rim joist, band joist or blocking to sill or top plate roof applications also. Nail each layer as follows: 32" o. Face nail at ends and at each splice. Edges inches h. Intermediate supports c, e inches.
Wood structural panels , subfloor, roof and interior wall sheathing to framing and particleboard wall sheathing to framing [see Table R Other wall sheathing g. Wood structural panels , combination subfloor underlayment to framing.
Intermediate supports inches. Wood structural panels subfloor, roof g and wall sheathing to framing and particleboard wall sheathing to framing f.
Body of panel d inches. Floor underlayment ; plywood-hardboard-particleboard f -fiber-cement h. Staple 18 ga. Staple 16 ga. Penetration inches. Edges inches o. Field inches o. Wind exposure category. Where siding is nailed to sheathing. Laterally unsupported stud height a feet. Maximum spacing where supporting a roof-ceiling assembly or a habitable attic assembly, only inches. Maximum spacing where supporting one floor, plus a roof- ceiling assembly or a habitable attic assembly inches. Maximum spacing where supporting two floors, plus a roof- ceiling assembly or a habitable attic assembly inches.
Maximum spacing where supporting one floor height a inches. Maximum spacing inches. Corners and intersecting walls. Butt joints in straight walls. Minimum nails each side of joint.
Building width c feet. Roof and ceiling. Roof, ceiling and one center- bearing floor. Roof, ceiling and one clear- span floor. Roof, ceiling and two center- bearing floors. Roof, ceiling, and two clear- span floors. Wood structural panel —one side. Wood structural panel —both sides. Detached, townhouse. SDC C. Up to 50 feet when length of required bracing per Table R Detached, townhouses , one- and two- story only. Up to 35 feet to allow for a single room not to exceed square feet.
Up to 35 feet when length of required bracing per Table R Ultimate Design Wind Speed mph. Story Location. Braced Wall Line Spacing c feet. Method LIB b. Exposure category d.
One- story structure. Two- story structure. Three- story structure. Roof eave-to- ridge height. Story height Section R Any story. Number of braced wall lines per plan direction c. Additional pound hold-down device. Top story only. Fastened to the end studs of each braced wall panel and to the foundation or framing below.
Interior gypsum board finish or equivalent. Omitted from inside face of braced wall panels. Gypsum board fastening. Seismic Design Category. Braced Wall Line Length feet c. Method LIB d. C townhouses only. Cripple wall below one- or two- story dwelling.
Story height Section Braced wall line spacing, townhouses in SDC C. Walls with stone or masonry veneer, townhouses in SDCC d, e. See Table R First and second story of two- story dwelling. LIB Let-in-bracing. Wood: per stud and top and bottom plates. DWB Diagonal wood boards. Exterior sheathing per Table R Interior sheathing per Table R SFB Structural fiberboard sheathing. GB Gypsum board. Nails or screws per Table R For all braced wall panel locations: 7" edges including top and bottom plates 7" field.
PCP Portland cement plaster. HPS Hardboard panel siding. ABW Alternate braced wall. PFH Portal frame with hold-downs. PFG Portal frame at garage. CS-G b, c Continuously sheathed wood structural panel adjacent to garage openings. CS-PF Continuously sheathed portal frame. Wall Height. Adjacent clear opening height inches.
Portal header height. Supporting one story and roof. Height of Braced Wall Panel. One story. First of two stories. Ultimate Design Wind Speed V ult mph. Length of short side feet c. Length of long side feet c. Wall bottom track to floor per Figure R Wall bottom track to foundation per Figure R Wall bottom track to wood sill per Figure R Steel plate spaced at 4' o.
Steel plate spaced at 3' o. Steel plate spaced at 2' o. Steel plate spaced at 1'-4" o. Wind uplift connector strength lbs c, e. The required length of bracing along each braced wall line shall be determined as follows:. Only braced wall panel s parallel to the braced wall line shall contribute toward the required length of bracing of that braced wall line.
Braced wall panel s along an angled wall meeting the minimum length requirements of Tables R Any braced wall panel on an angled wall at the end of a braced wall line shall contribute its projected length for only one of the braced wall lines at the projected corner. Exception: The length of wall bracing for dwellings in Seismic Design Categories D 0 , D 1 and D 2 with stone or masonry veneer installed in accordance with Section R Features Overview.
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Sign in. The required length of bracing along each braced wall line shall be determined as follows: All buildings in Seismic Design Categories A and B shall use Table R Linear interpolation shall be permitted.
Method LIB shall have gypsum board fastened to not less than one side with nails or screws in accordance with Table R Spacing of fasteners at panel edges shall not exceed 8 inches. Where three or more parallel braced wall lines are present and the distances between adjacent braced wall lines are different, the average dimension shall be permitted to be used for braced wall line spacing. Section R The total adjustment factor is the product of all applicable adjustment factors.
The adjustment factor is permitted to be 1. The same adjustment factor shall be applied to all braced wall lines on all floors of the structure, based on the worst-case exposure category. Wall bracing lengths are based on a soil site class "D. Where the braced wall line length is greater than 50 feet, braced wall lines shall be permitted to be divided into shorter segments having lengths of 50 feet or less, and the amount of bracing within each segment shall be in accordance with this table.
Where more than one bracing method is used, mixing methods shall be in accordance with Section R Interior gypsum board. The total length of bracing required for a given wall line is the product of all applicable adjustment factors. Applies to stone or masonry veneer exceeding the first story height. The adjustment factor for stone or masonry veneer shall be applied to all exterior braced wall lines and all braced wall lines on the interior of the building, backing or perpendicular to and laterally supporting veneered walls.
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