NORTH CAROLINA BUILDING CODE COUNCIL 2012 NC Building, Fire, Fuel Gas and Residential Code Changes

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1 NORTH CAROLINA BUILDING CODE COUNCIL 2012 NC Building, Fire, Fuel Gas and Residential Code Changes Agency Contact: Barry Gupton, Chief Code Consultant, Rules Coordinator, x 232. Authority for Rule-making: G.S ; Impact Summary: State Government Impact: Unclear Local Government Impact: Unclear Substantial Economic Impact: Unclear Reason for Proposed Action: To incorporate changes in the NC State Building Codes as a result of rulemaking petitions filed with the NC Building Code Council and to incorporate changes proposed by the Council. Summary of Proposed Actions and Their Impact: 1. Request by Christopher Havanas, with GOJO Industries, Inc., to amend the 2012 NC Fire Code, Section , number 5. The proposed amendment is as follows: Section Alcohol-based hand rubs classified as Class I or II liquids. The use of wall-mounted dispensers containing alcohol-based hand rubs classified as Class I or II liquids shall be in accordance with all of the following: (no change to items 1 through 4, 6 through 7) 5. Dispensers shall not release their contents except when the dispenser is manually activated. Exception: Facilities shall be permitted to install and use automatically activated touch free alcoholbased hand rub dispensing devices with the following requirements: 1. The facility or persons responsible for the dispensers shall test the dispensers each time a new refill is installed in accordance with the manufacturer s care and use instructions. 2. Dispensers shall be designed and must operate in a manner that ensures accidental or malicious activations of the dispensing device are minimized. At a minimum, all devices subject to or used in accordance with this section shall have the following safety features: 2.1 Any activations of the dispenser shall occur when an object is placed within 4 inches of the sensing device. 2.2 The dispenser shall not dispense more than the amount required for hand hygiene consistent with the label instructions as regulated by the United States Food and Drug Administration (US FDA).

2 An object placed within the activation zone and left in place will cause only one activation. Motion Al Bass/Second Lon McSwain/Granted The request was granted unanimously and sent to the Administrative/Fire Committees for review. Reason Given The proposal represents the language contained in the 2012 IFC and the 2012 NFPA 101. It defines the engineering parameters for safe operation of touch free systems while ensuring facilities have access to current touch free technologies that promote hand hygiene compliance. The proposed effective date of this rule is January 1, Fiscal Statement This rule is anticipated to provide equivalent compliance with little change in cost. There would be little additional cost from installing and operating an automatic versus a manual dispenser. The initial cost of the automatic dispenser may be $5-10 more expensive (based on Staples s prices) than that of the manual. The automatically activated alcohol-based hand rub dispensing devices, however, have been gaining traction and, as a result of increased demand, their cost per use is close to that of the manual units. The major cost difference comes from the batteries required for the automated dispenser; however, given that a set of batteries costing about $12 is functional for about 30,000 uses, the additional cost per use from the battery is marginal. The difference in the cost of refills is about $3-5 for a 2,000-uses refill. 1 The additional time required by the rule change to ensure the touch-free dispensers function properly is negligible. Dispensers are already built to ensure that accidental or malicious activation is minimized. If the regulated community opts for the automated versus the manual dispensers, the touch-free feature might provide an added benefit in terms of reduced health risks to users. The benefits can be significant, especially if the touch-free dispensers are used in hospitals. A 2005 study in a pediatric hospital setting found that people are 30% more likely to use the touch-free sanitizer dispensers than the manual. 2 Another study looking at hand hygiene noncompliance as it relates to health care associated infections (like Methicillin-Resistant Staphylococcus Aureus, MRSA) determined that the cost per noncompliance event is $1.98 and the noncompliance rate was about 15 events per day. 3 Since it is unclear whether these results would translate to settings other than hospitals and how many regulated entities would opt for the automated versus the manual dispenser, it is difficult to quantify the incremental benefit from an automated dispenser. This rule is not expected to either have a substantial economic impact. It is unclear whether 1 Based on uses per battery and uses per sanitizer refill information available on the Uline Shipping Specialists. supply specialists - the automatic unit cost is $27 including batteries for uses 2 Larson EL, Albrecht S, O Keefe M. Hand hygiene behavior in a pediatric emergency department and a pediatric intensive care unit: comparison of use of 2 dispenser systems. American Journal of Critical Care, 2005 Jul;14(4): Keith L. Cummings, et. Al. Hand Hygiene Noncompliance and the Cost of Hospital-Acquired Methicillin-Resistant Staphylococcus Aureus Infection Infection Control and Hospital Epidemiology Apr. 2010; 31(4):

3 state or local government buildings would opt for the automated dispenser, thereby potentially creating a state or local impact. 2. Request by Lon McSwain, NC Building Code Council, to amend the 2012 NC Building Code, Section The proposed amendment is as follows: Minimum required egress width. The means of egress width shall not be less than required by this section. The total width of means of egress in inches (mm) shall not be less than the total occupant load served by the means of egress multiplied by 0.3 inch (7.62 mm) per occupant for stairways and by 0.2 inch (5.08 mm) per occupant for other egress components. The width shall not be less than specified elsewhere in this code. Multiple means of egress shall be sized such that the loss of any one means of egress shall not reduce the available capacity to less than 50 percent of the required capacity. The maximum capacity required from any story of a building shall be maintained to the termination of the means of egress. Exception: Means of egress complying with Section Exceptions: 1. Means of egress complying with Section For other than Group H and I-2 occupancies, the capacity, in inches (mm), of means of egress stairways shall be calculated by multiplying the occupant load served by the stairway by a means of egress capacity factor of 0.2 inch (5.1 mm) per occupant in buildings equipped throughout with an automatic sprinkler system installed in accordance with Section or and an emergency voice/alarm communications system in accordance with Section For other than Group H and I-2 occupancies, the capacity, in inches (mm), of means of egress components other than stairways shall be calculated by multiplying the occupant load served by such components by a means of egress capacity factor of 0.15 inch (3.8 mm) per occupant in buildings equipped throughout with an automatic sprinkler system installed in accordance with Section or and an emergency voice/alarm communications system in accordance with Section Motion Kim Reitterer/Second John Hitch/Granted The request was granted unanimously. Reason Given To provide prescriptive exceptions for compliance with means of egress capacity, and therefore provide more flexibility to the Code. The current basic Code requirement for egress (staircase) width assumes that the building does not have sprinklers or notification. The proposed exceptions would allow a reduction in egress width with the addition of an automatic sprinkler system and an emergency voice/alarm communication system. The trade-off is faster notification (alarm) and more time to exit (sprinklers) in exchange for less exit width. The proponent believes this trade-off would not compromise safety. The proposed effective date of this rule is January 1, 2015.

4 Fiscal Statement: This proposed rule is anticipated to provide equivalent compliance with no net increase in costs. The type of the buildings that would opt for this exception would likely be new, multilevel, Assembly use buildings with over 1000 occupants. Assembly type buildings include indoor and outdoor sporting venues, performance venues, and eating, amusement, or worshiping establishments, The Code currently includes minimum requirements for stair width, so this change would likely affect only multiple story new Assembly buildings with high occupant loads that would prefer to install the communication system and have narrower exit staircases that increase the useable space of the structure. State wide data regarding the number of multilevel new Assembly buildings, however, is not readily available. Based on data provided by Durham County, no multilevel, new building was issued a permit in the last three years. Whoever would opt for a narrower egress accompanied by an alarm and sprinkler system might incur net construction savings related to building a smaller mode of egress and would incur benefits from increasing the useable space in the building. They would also incur costs related to installing an alarm and sprinkler system. The American Fire Sprinkler Association estimates that generally the cost for the sprinklers would be around $1-2 per square foot. 4 The rule of thumb for a fire alarm system in a commercial building is about $ per square foot (inflated from 2004 level using IHS Global Insight Consumer Price Index forecast). 5 The total cost can vary greatly depending on the size and occupancy of the building, which can range from 10,000 (based on data from Durham County regarding renovation permits for large Assembly buildings and one-story Assembly permits in the last three years) to 700,000 square foot (size of PNC Arena in Raleigh). Assuming 10,000 square foot multilevel Assembly building, the cost of the alarm and sprinkler system would be about $16,000-32,000; for a 700,000 square foot building the cost would be $1.1-$2.2 million. It is unclear if this rule change would have an state or local impact since it is uncertain if new state or local government buildings would opt for the exception. Although, the impact is ultimately unknown, the agency does not expected this rule change to have a substantial economic impact, given the small number of new, multilevel Assembly buildings that could benefit from the rule change. 3. Request by Ralph Euchner, NC Building Code Council, to amend the 2012 NC Fuel Gas Code, Section The proposed amendment is as follows: 4 American Fire Sprinkler Association. Frequently Asked Questions. 5 Robert Tranford. How to Estimate the Cost of a Commercial Fire Alarm System. American Society of Professional Estimators. May

5 CSST. Corrugated stainless steel tubing (CSST) gas piping systems shall be bonded to the electrical service grounding electrode system at the point where the gas service enters the building. The bonding jumper shall be not smaller than 6 AWG copper wire or equivalent. Motion David Smith/Second Al Bass/Granted The request was granted unanimously. Reason Given To remove language that requires additional runs of bonding wire where it may not be necessary. The proposed effective date of this rule is January 1, Fiscal Statement This rule is anticipated to provide equivalent compliance with no net decrease/increase in cost. This rule is not expected to either have a substantial economic impact or affect local and state funds. 4. Request by David Smith, NC Building Code Council, to amend the 2012 NC Residential Code, Section R The proposed amendment is as follows: Replace the 2012 NC Residential Code Sections R through R with the attached Revised Wall Bracing Provisions of the 2012 North Carolina Residential Code. Please see R Wall Bracing Document in Appendix Motion Al Bass/Second David Smith/Granted The request was granted unanimously. Reason Given This is a reorganization and restructuring of the wall bracing provisions of the NC Residential Code to improve its readability. The proposed effective date of this rule is January 1, Fiscal Statement The benefit of this rule change is that the wall bracing requirements will be easier to understand for both the regulated community and building inspectors making compliance and enforcement more efficient. Consequently, there is a chance that the durability of the building might increase. Both parties would incur some time savings, although it is difficult to estimate what the value of that might be given the lack of data in this respect. Since the actual requirements for wall bracing are not changing, the proposed rule is anticipated to provide equivalent compliance, or even a higher level of compliance, with no increase in cost. This rule is not expected to either have a substantial economic impact or affect local and state funds since it is aimed at single family dwellings. The International Residential Code has already adopted this amendments for ease of use, and there has not been a substantial impact as a result.

6 Revised Wall Bracing Provisions of the 2012 North Carolina Residential Code R Wall bracing. 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 The building official may require the permit applicant to identify and locate on the construction documents braced wall lines and braced wall panels as described herein. R Braced wall lines. 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. R Length of a braced wall line. The length of a braced wall line shall be the distance between its ends. The end of a braced wall line shall be the intersection with a perpendicular braced wall line, an angled braced wall line as permitted in Section R or an exterior wall as shown in Figure R BWL A SPACING BWL B SPACING BWL C BETWEEN BETWEEN BWL A-B BWL B-C BWL A SPACING BWL B SPACING BWL C BETWEEN BETWEEN BWL A-B BWL B-C BWL 1 SPACING BETWEEN BWL 1-3 BWL 3 4' MAX 4' MAX 4' MAX 4' MAX 4' MAX 4' MAX TYPICAL FIRST FLOOR BRACED WALL PLAN BWL 4 BWL 2 BWL 1 SPACING BETWEEN BWL 1-2 SPACING BETWEEN BWL 2-4 END OF BUILDING SPACING BETWEEN BWL 1 BWL 1 AND END OF BUILDING 4' MAX 4' MAX NO BRACED WALL LINE; ROOF AND FLOOR BEAR AT SAME ELEVATION NOTE: IN THE ABSENCE OF A BRACED WALL LINE, BWL A, B, C SHALL END AT EXTERIOR WALL 4' MAX TYPICAL UPPER FLOOR BRACED WALL PLAN For SI: 1 foot=304.8mm FIGURE R BRACED WALL LINES R Offsets along a braced wall line. All exterior walls parallel to a braced wall line shall be permitted to offset up to 4 feet (1219 mm) from the designated braced wall line location as shown Figure R Interior walls used as bracing shall be permitted to offset up to 4 feet (1219 mm) from a braced wall line through the interior of the building as shown in Figure R R Spacing of braced wall lines. There shall be a minimum of two braced wall lines in both the longitudinal and transverse direction as shown in Figure R Intermediate braced wall lines through the interior of the building shall be permitted. The spacing between parallel braced wall lines shall be in accordance with Table R R Angled walls. Any portion of a wall along a braced wall line shall be permitted to angle out of plane for a maximum diagonal length of 8 feet (2438 mm). Where the angled wall occurs at a corner, the length of the braced wall line shall be measured from the projected corner as shown in Figure R Where the diagonal length is greater than 8 feet (2438 mm), it shall be considered a separate braced wall line and shall be braced in accordance with Section R Revised Wall Bracing Provisions 2012 NC Residential Code 1

7 TABLE R BRACED WALL LINE SPACING BRACED WALL LINE SPACING CRITERIA APPLICATION CONDITION BUILDING TYPE Maximum Exception to Maximum Spacing Spacing Wind bracing Seismic bracing For SI: 1 foot = mm 85 mph to <110 mph Detached, townhouse 60 feet None SDC A - C Detached Use wind bracing SDC A B Townhouse Use wind bracing SDC C Townhouse 35 feet Up to 50 feet when length of required bracing per Table R (3) is adjusted in accordance with Table R (4) PROJECTED CORNER BRACED WALL LINE 1 PROJECTED LENGTH OF BRACING BRACED WALL LINE 2 8' MAX. TYP. NOTE: IF THE DIAGONAL WALL IS GREATER THAN 8 FEET LONG, THEN IT MUST BE TREATED AS A SEPARATE BRACED WALL LINE. For SI: 1 foot=304.8 mm FIGURE R ANGLED WALLS R Braced wall panels. Braced wall panels shall be full-height sections of wall that shall have no vertical or horizontal offsets. Braced wall panels shall be constructed and placed along a braced wall line in accordance with this section and the bracing methods specified in Section R R Braced wall panel uplift load path. The bracing lengths in Table R (1) apply only when uplift loads are resisted per Section R R Locations of braced wall panels. A braced wall panel shall begin within 10 feet (3810 mm) from each end of a braced wall line as determined in accordance with Section R The distance between adjacent edges of braced wall panels along a braced wall line shall be no greater than 20 feet (6096 mm) as shown in Figure R Revised Wall Bracing Provisions 2012 NC Residential Code 2

8 BRACED WALL BRACED WALL 10' MAX 20' MAX 10' MAX BWL 3 BWL 2 BWL 1 20' MAX BRACED WALL BRACED WALL BWL A BWL B BWL >16' REQUIRES MINIMUM OF 2 S 10' MAX 10' MAX BRACED WALL BRACED WALL NOTE: CONTINUOUS SHEATHING METHODS REQUIRES ALL FRAMED PORTIONS OF THE BRACED WALL LINE TO BE SHEATHED. BRACED WALL 20' MAX BRACED WALL 20' MAX BRACED WALL For SI: 1 foot=304.8 mm FIGURE R LOCATION OF S R Minimum number of braced wall panels. Braced wall lines with a length of 16 feet (4877 mm) or less shall have a minimum of two braced wall panels of any length or one braced wall panel equal to 48 inches (1219 mm) or more. Braced wall lines greater than 16 feet (4877 mm) shall have a minimum of two braced wall panels. R Required length of bracing. The required length of bracing along each braced wall line shall be determined as follows. 1. All buildings in Seismic Design Categories A and B shall use Table R (1) and the applicable adjustment factors in Table R (2). 2. Detached buildings in Seismic Design Category C shall use Table R (1) and the applicable adjustment factors in Table R (2). 3. Townhouses in Seismic Design Category C shall use the greater value determined from Table R (1) or R (3) and the applicable adjustment factors in Table R (2) or R (4) respectively. Only braced wall panels parallel to the braced wall line within the 4 foot (1219 mm) offset permitted by Section R shall contribute towards the required length of bracing of that braced wall line. If a braced wall panel is located along an angled wall and meets the minimum length requirements of Tables R or R , it shall be permitted to contribute its projected length towards the minimum required length of bracing for the braced wall line as shown in Figure R If a braced wall panel is located along an angled wall at the end of a braced wall line, it shall contribute its projected length for only one of the braced wall lines at the projected corner. Revised Wall Bracing Provisions 2012 NC Residential Code 3

9 EXPOSURE CATEGORY B 30 FT MEAN ROOF HEIGHT 10 FT EAVE TO RIDGE HEIGHT 10 FT WALL HEIGHT 2 BRACED WALL LINES Basic Wind Speed (mph) Story Location TABLE R (1) BRACING REQUIREMENTS BASED ON WIND SPEED Braced Wall Line Spacing (feet) MINIMUM TOTAL LENGTH (FEET) OF S REQUIRED ALONG EACH BRACED WALL LINE a Method LIB b Method GB Methods DWB, WSP, SFB, PBS, PCP, HPS, CS- SFB c Methods CS-WSP, CS-G, CS-PF NP NP NP NP NP NP NP NP NP NP NP NP < 110 d NP NP NP NP NP NP For SI: 1 inch = 25.4 mm, 1 foot = 305 mm. a. Linear interpolation shall be permitted. b. Method LIB shall have gypsum board fastened to at least one side with nails or screws per Table R602.3(1) for exterior sheathing or Table R for interior gypsum board. Spacing of fasteners at panel edges shall not exceed 8 inches (203 mm). c. Method CS-SFB does not apply where the wind speed is greater than 100 mph. Revised Wall Bracing Provisions 2012 NC Residential Code 4

10 TABLE R (2) WIND ADJUSTMENT FACTORS TO THE REQUIRED LENGTH OF WALL BRACING ADJUSTMENT BASED ON Exposure category Roof eave-to-ridge height Wall height adjustment Number of braced wall lines (per plan direction) C Additional 800 lb hold-down device Interior gypsum board finish (or equivalent) STORY/ SUPPORTING One story structure Two-story structure Three-story structure Roof only Roof + 1 floor Roof + 2 floors Any story Any story Top story only Any story ADJUSTMENT FACTOR a,b CONDITION (multiply length from Table R (1) by this factor) B 1.00 C 1.20 D 1.50 B 1.00 C 1.30 D 1.60 B 1.00 C 1.40 D ft ft ft ft ft ft ft ft ft ft ft ft Not permitted 8 ft ft ft ft ft Fastened to the end studs of each braced wall panel and to the foundation or framing below Omitted from inside face of braced wall panels APPLICABLE METHODS All methods DWB, WSP, SFB, PBS, PCP, HPS DWB, WSP, SFB, PBS, PCP, HPS, CS-WSP, CS-G, CS-SFB Gypsum board fastening Any story 4 in. o.c. at panel edges, including top and bottom plates, and all horizontal joints blocked 0.7 GB For SI: 1 foot = 305 mm, 1 lb = 4.48 N. a. Linear Interpolation shall be permitted. b. The total adjustment factor is the product of all applicable adjustment factors. c. The adjustment factor is permitted to be 1.0 when determing bracing amounts of intermediate braced wall lines provided the bracing amounts on adjacent braced wall lines are based on a spacing and number that neglects the intermediate braced wall line. Revised Wall Bracing Provisions 2012 NC Residential Code 5

11 SOIL CLASS D b WALL HEIGHT = 10 FT 10 PSF FLOOR DEAD LOAD 15 PSF ROOF/CEILING DEAD LOAD BRACED WALL LINE SPACING 25 FT Seismic Design Category C (townhouses only) Story Location TABLE R (3) BRACING REQUIREMENTS BASED ON SEISMIC DESIGN CATEGORY Braced Wall Line Length (ft) MINIMUM TOTAL LENGTH (FEET) OF S REQUIRED ALONG EACH BRACED WALL LINE a Method LIB c Method GB Methods DWB, SFB, PBS, PCP, HPS, CS-SFB Method WSP Methods CS-WSP, CS-G, NP NP NP NP NP NP NP NP NP NP For SI: 1 foot 305 mm a. Linear interpolation shall be permitted. b. Wall bracing lengths are based on a soil site class D. Interpolation of bracing length between the S ds values associated with the Seismic Design Categories shall be permitted when a site-specific S ds value is determined in accordance with Section of the International Building Code. c. Method LIB shall have gypsum board fastened to at least one side with nails or screws per Table R602.3(1) for exterior sheathing or Table R for interior gypsum board. Spacing of fasteners at panel edges shall not exceed 8 inches (203 mm). TABLE R (4) SEISMIC ADJUSTMENT FACTORS TO THE REQUIRED LENGTH OF WALL BRACING ADJUSTMENT FACTOR a,b STORY/ CONDITION (Multiply length SUPPORTING from Table R (3) by this factor) ADJUSTMENT BASED ON: Story height 10 ft 1.0 Any story (Section 301.3) >10 ft 12 ft 1.2 Braced wall line spacing Any story 35 ft 1.0 >35 ft 50 ft 1.43 Wall dead load Any story > 8 ft < 15 ft 1.0 <8 psf 0.85 Any story < 15 psf 1.0 Roof/ceiling dead load for Roof plus one or two stories >15 psf 25 psf 1.1 wall supporting Roof only >15 psf 25 psf APPLICABLE METHODS All methods Walls with stone or masonry veneer 1.5 Interior gypsum board finish (or equivalent) Any story Omitted from inside face of braced wall panels Revised Wall Bracing Provisions 2012 NC Residential Code DWB, WSP, SFB, PBS, PCP, HPS,CS-WSP, CS-G,CS-SFB For SI: 1 psf = 47.8 N/m 2. a. Linear interpolation shall be permitted. b. The total length of bracing required for a given wall line is the product of all applicable adjustment factors. c. The length-to-width ratio for the floor/roof diaphragm shall not exceed 3:1. The top plate lap splice nailing shall be a minimum of 12-16d nails on each side of the splice. d. Applies to stone or masonry veneer exceeding the first story height. e. 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. R Bracing methods for braced wall panels. Braced wall panels shall be constructed in accordance with this section and the methods listed in Table R

12 Intermittent Bracing Methods METHODS, MATERIAL LIB Let-in-bracing DWB Diagonal wood boards WSP Wood structural panel (See Section R604) SFB Structural fiberboard sheathing GB Gypsum board PBS Particleboard sheathing (See Section R605) PCP Portland cement plaster HPS Hardboard panel siding ABW Alternate braced wall MINIMUM THICKNESS 1x4 wood or approved metal straps at 45 to 60 angles for maximum 16 stud spacing ¾ (1 nominal) for maximum 24 stud spacing 3 / 8" 1 / 2" or 25 / 32" for maximum 16" stud spacing 1 / 2" 3 / 8" or 1 / 2" for maximum16" stud spacing See Section R703.6 for maximum 16 stud spacing 7 / 16" for maximum 16 stud spacing 3 / 8" TABLE R BRACING METHODS FIGURE CONNECTION CRITERIA a Fasteners Spacing Wood: 2-8d common nails or 3-8d (2 Wood: per stud and top ½ long x dia.) nails and bottom plates Metal: per manufacturer Metal: per manufacturer 2-8d (2½" long x 0.113" dia.) nails or 2-1¾" long staples Exterior sheathing per Table R602.3(3) Interior sheathing per Table R602.3(1) or R602.3(2) Per stud 6" edges 12" field Varies by fastener 1½" long x 0.12" dia. (for ½ thick 3" edges sheathing) 1 3 / 4 long x 0.12 dia. (for 6" field 25 / 32 thick sheathing) galvanized roofing nails or 8d common (2½" long x 0.131" dia.) nails Nails or screws per Table R602.3(1) for exterior locations Nails or screws per Table R for interior locations For 3/8, 6d common (2 long x 0.113" dia.) nails; for ½, 8d common (2½" long x 0.131" dia.) nails 1½" long, 11 gage, 7 / 16" dia. head nails or 7 / 8" long, 16 gage staples 0.092" dia., 0.225" dia. head nails with length to accommodate 1½" penetration into studs See Section R For all braced wall panel locations: 7" edges (including top and bottom plates), 7" field 3" edges 6" field 6" o.c. on all framing members 4" edges 8" field See Section R PFH Portal frame with hold-downs 3 / 8 See Section R See Section R PFG Portal frame at garage 7 / 16" See Section R See Section R Continuous Sheathing Methods CS-WSP Continuously sheathed wood structural panel CS-G b, c Continuously sheathed wood structural panel adjacent to garage openings CS-PF Continuously sheathed portal frame CS-SFB d Continuously sheathed structural fiberboard 3 / 8" 3 / 8" 7 / 16" 1 / 2" or 25 / 32" for maximum 16" stud spacing Exterior sheathing per Table R602.3(3) Interior sheathing per Table R602.3(1) or R602.3(2) See Method CS-WSP See Section R " edges 12" field Varies by fastener See Method CS-WSP See Section R ½" long x 0.12" dia. (for ½ thick 3" edges sheathing) 1 3 / 4 long x 0.12 dia. (for 6" field 25 / 32 thick sheathing) galvanized roofing nails or 8d common (2½" long x dia.) nails For SI: 1 inch = 25.4 mm, 1 foot = 305 mm. a. Adhesive attachment of wall sheathing, including Method GB, shall not be permitted in townhouses in Seismic Design Category C. b. Applies to panels next to garage door opening when supporting gable end wall or roof load only. May only be used on one wall of the garage. c. Garage openings adjacent to a Method CS-G panel shall be provided with a header in accordance with Table R502.5(1). A full height clear opening shall not be permitted adjacent to a Method CS-G panel. d. Method CS-SFB does not apply in areas where the wind speed exceeds 100 mph. Revised Wall Bracing Provisions 2012 NC Residential Code 7

13 R Mixing methods. Mixing of bracing methods shall be permitted as follows: 1. Mixing intermittent bracing and continuous sheathing methods from story to story shall be permitted. 2. Mixing intermittent bracing methods from braced wall line to braced wall line within a story shall be permitted. In regions where the basic wind speed is less than or equal to 100 mph, mixing of intermittent bracing and continuous sheathing methods from braced wall line to braced wall line within a story shall be permitted. 3. 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 the length of required bracing in accordance with Table R (1) or R (3) is the highest value of all intermittent bracing methods used. 4. Mixing of continuous sheathing methods CS-WSP, CS- G and CS-PF along a braced wall line shall be permitted. 5. In Seismic Design Categories A and B, and for detached one- and two-family dwellings in Seismic Design Category C, mixing of intermittent bracing methods along the interior portion of a braced wall line with continuous sheathing methods CS-WSP, CS-G and CS-PF along the exterior portion of the same braced wall line shall be permitted. The length of required bracing shall be the highest value of all intermittent bracing methods used in accordance with Table R (1) or R (3) as adjusted by Tables R (2) and R (4), respectively. The requirements of Section R shall apply to each end of the continuously sheathed portion of the braced wall line. R Continuous sheathing methods. 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 R Braced wall panel interior finish material. Braced wall panels shall have gypsum wall board installed on the side of the wall opposite the bracing material. Gypsum wall board shall be not less than ½ inch (12.7 mm) in thickness and be fastened with nails or screws in accordance with Table R602.3(1) for exterior sheathing or Table R for interior gypsum wall board. Spacing of fasteners at panel edges for gypsum wall board opposite Method LIB bracing shall not exceed 8 inches (203 mm). Interior finish material shall not be glued in townhouses in Seismic Category C. Exceptions: 1. Interior finish material is not required opposite wall panels that are braced in accordance with Method GB, ABW, PFH, PFG and CS-PF, unless otherwise required by Section R An approved interior finish material with an inplane 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 the required length of bracing in Tables R (1) and R (3) is multiplied by the appropriate adjustment factor in Tables R (2) and R (4) respectively, unless otherwise required by Section R R Minimum length of a braced wall panel. The minimum length of a braced wall panel shall comply with Table R For Methods CS-WSP and CS-SFB, the minimum panel length shall be based on the vertical dimension of the adjacent opening in accordance with Table R and Figure R When a panel has openings on either side of differing heights, the larger vertical dimension shall be used to determine the minimum braced wall panel length. R Contributing length. For purposes of complying with the required length of bracing in Tables R (1) and R (3), the contributing length of each braced wall panel to the total length of bracing shall be as specified in Table R Revised Wall Bracing Provisions 2012 NC Residential Code 8

14 METHOD (See Table R ) TABLE R MINIMUM LENGTH OF S MINIMUM LENGTH a (in) Wall Height CONTRIBUTING LENGTH (in) PFH DWG, WSP, SFB, PBS, PCP, HPS CS-WSP, CS-SFB 8 ft 9 ft 10 ft 11 ft 12 ft Actual b GB Double sided = Actual Single sided = 0.5 x Actual LIB NP NP Actual b ABW Supporting roof only c 20 c 48 Supporting one story and roof c 29 c 48 PFG c 36 c 1.5 x Actual b CS-G Actual b CS-PF c 24 c Actual b Adjacent opening vertical dimension (in) For SI: 1 inch = 25.4 mm NP = Not permitted a. Linear interpolation shall be permitted. b. Use the actual length provided it is greater than or equal to the minimum length. c. Maximum header height for is 10 ; however, wall height may be increased to 12 with a pony wall per Table R Actual b OPENING VERTICAL DIMENSION OPENING VERTICAL DIMENSION OPENING VERTICAL DIMENSION LENGTH LENGTH FIGURE R S WITH CONTINUOUS SHEATHING LENGTH Revised Wall Bracing Provisions 2012 NC Residential Code 9

15 R Partial credit. For Methods DWB, WSP, SFB, PBS, PCP and HPS panels between 36 inches and 48 inches in length shall be considered a braced wall panel and shall be permitted to partially contribute towards the required length of bracing in Table R (1) and R (3), and the contributing length shall be determined from Table R TABLE R PARTIAL CREDIT FOR S LESS THAN 48 INCHES IN ACTUAL LENGTH Actual Length of Braced Contributing Length of Braced Wall Panel (in) a Wall Panel (in) 8 ft Wall Height 9 ft Wall Height N/A For SI: 1 inch = 25.4mm a Linear interpolation shall be permitted. R Construction of Methods ABW, PFH, PFG and CS-PF. Methods ABW, PFH, PFG and CS-PF shall be constructed as specified in Sections R through R LENGTH PER TABLE R R Method ABW: Alternate braced wall panels. Method ABW braced wall panels shall be constructed in accordance with Figure R HEIGHT MIN. 3/8" WOOD STRUCTURAL SHEATHING ON ONE FACE MIN. 2X4 FRAMING. MIN. DOUBLE STUDS REQUIRED. (2) HOLD-DOWN OR (2) STRAP-TYPE ANCHORS WITH A MINIMUM CAPACITY OF 3,600 LBS (ONE OF EACH SHOWN FOR CLARITY). STRAP-TYPE ANCHORS SHALL BE PERMITTED TO BE ATTACHED OVER THE WOOD STRUCTURAL MUST BE ATTACHED TO CONCRETE FOOTING OR CONCRETE FOUNDATION WALL CONTINUOUS OVER BRACED WALL LINE FOR SPLICE (IF NEEDED) ADJOINING EDGES SHALL MEET OVER AND BE FASTENED TO COMMON FRAMING 8D COMMON OR GALV. BOX 6" O.C. AT EDGES. FOR SINGLE STORY 4" O.C. EDGES FOR THE FIRST OF 2 STORIES STUDS UNDER HEADER AS REQUIRED 8D COMMON OR GALV. BOX 12" O.C. AT INTERIOR SUPPORTS MIN. REINFORCING OF FOUNDATION, ONE #4 BAR TOP AND BOTTOM. LAP BARS 15'' MINIMUM. (2) 1/2" DIAMETER ANCHOR BOLTS LOCATED BETWEEN 6" AND 12" OF EACH END OF THE SEGMENT MINIMUM FOOTING SIZE UNDER OPENING IS 12" X 12". A TURNED-DOWN SLAB SHALL BE PERMITTED AT DOOR OPENINGS. For SI: 1 inch = 25.4 mm, 1 foot = 305 mm FIGURE R METHOD ABW: ALTERNATE Revised Wall Bracing Provisions 2012 NC Residential Code 10

16 R Method PFH: Portal frame with holddowns. Method PFH braced wall panels shall be constructed in accordance with Figure R R Method PFG: Portal frame at garage door openings. Where supporting a roof or one story and a roof, a Method PFG braced wall panel constructed in accordance with Figure R shall be permitted on either side of garage door openings. R Method CS-PF: Continuously sheathed portal frame. Continuously sheathed portal frame braced wall panels shall be constructed in accordance with Figure R and Table R The number of continuously sheathed portal frame panels in a single braced wall line shall not exceed four. EXTENT OF HEADER WITH DOUBLE PORTAL FRAMES (TWO S) EXTENT OF HEADER WITH SINGLE PORTAL FRAME (ONE ) 2' -18' FINISHED WIDTH OF OPENING FOR SINGLE OR DOUBLE PORTAL PONY WALL HEIGHT TENSION STRAP PER TABLE R (ON OPPOSITE SIDE OF SHEATHING) 12' MAX TOTAL WALL HEIGHT 10' MAX. HEIGHT MIN. 3" X 11-1/4" NET HEADER STEEL HEADER PROHIBITED FASTEN SHEATHING TO HEADER WITH 8D COMMON OR GALVANIZED BOX NAILS IN 3" GRID PATTERN AS SHOWN HEADER TO JACK-STUD STRAP PER TABLE R ON BOTH SIDES OF OPENING OPPOSITE SIDE OF SHEATHING MIN. DOUBLE 2X4 FRAMING COVERED WITH MIN. 3/8" THICK WOOD STRUCTURAL SHEATHING WITH 8D COMMON OR GALVANIZED BOX NAILS AT 3" O.C. IN ALL FRAMING (STUDS, BLOCKING, AND SILLS) TYP. MIN. LENGTH OF PER TABLE R MIN. (2) 4200 LB STRAP-TYPE HOLD-DOWNS (EMBEDDED INTO CONCRETE AND NAILED INTO FRAMING) IF NEEDED, SPLICE EDGES SHALL OCCUR OVER AND BE NAILED TO COMMON BLOCKING WITHIN MIDDLE 24" OF WALL MID- HEIGHT. ONE ROW OF 3" O.C. NAILING IS REQUIRED IN EACH EDGE. TYPICAL PORTAL FRAME CONSTRUCTION MIN. DOUBLE 2x4 POST (KING AND JACK STUD). NUMBER OF JACK STUDS PER TABLES R502.5(1) & (2). FASTEN TOP PLATE TO HEADER WITH TWO ROWS OF 16D SINKER NAILS AT 3" O.C. TYP. MIN. 3/8" WOOD STRUCTURAL SHEATHING MIN. REINFORCING OF FOUNDATION, ONE #4 BAR TOP AND BOTTOM OF FOOTING. LAP BARS 15'' MINIMUM. MIN LB HOLD-DOWN DEVICE (EMBEDDED INTO CONCRETE AND NAILED INTO FRAMING MIN. FOOTING SIZE UNDER OPENING IS 12" X 12". A TURNED- DOWN SLAB SHALL BE PERMITTED AT DOOR OPENINGS. MIN. (1) 5/8" DIAMETER ANCHOR BOLT INSTALLED PER R WITH 2"x2"x3/16" PLATE WASHER FRONT ELEVATION For SI: 1 inch = 25.4 mm, 1 foot = 305 mm SECTION FIGURE R METHOD PFH: PORTAL FRAME WITH HOLD-DOWNS Revised Wall Bracing Provisions 2012 NC Residential Code 11

17 EXTENT OF HEADER WITH DOUBLE PORTAL FRAMES (TWO S) EXTENT OF HEADER WITH SINGLE PORTAL FRAME (ONE ) 2' -18' FINISHED WIDTH OF OPENING FOR SINGLE OR DOUBLE PORTAL PONY WALL HEIGHT MIN. 3" X 11-1/4" NET HEADER STEEL HEADER PROHIBITED TENSION STRAP PER TABLE (ON OPPOSITE SIDE OF SHEATHING) 12' MAX TOTAL WALL HEIGHT 10' MAX. HEIGHT FASTEN SHEATHING TO HEADER WITH 8D COMMON OR GALVANIZED BOX NAILS IN 3" GRID PATTERN AS SHOWN HEADER TO JACK-STUD STRAP PER TABLE R ON BOTH SIDES OF OPENING OPPOSITE SIDE OF SHEATHING MIN. DOUBLE 2X4 FRAMING COVERED WITH MIN. 7/16" THICK WOOD STRUCTURAL SHEATHING WITH 8D COMMON OR GALVANIZED BOX NAILS AT 3" O.C. IN FRAMING (STUDS AND SILLS) AS SHOWN, TYP. IF NEEDED, SPLICE EDGES SHALL OCCUR OVER AND BE NAILED TO COMMON BLOCKING WITHIN 24" OF THE WALL MID- HEIGHT. ONE ROW OF 3" O.C. NAILING IS REQUIRED IN EACH EDGE. TYPICAL PORTAL FRAME CONSTRUCTION FASTEN TOP PLATE TO HEADER WITH TWO ROWS OF 16D SINKER NAILS AT 3" O.C. TYP. MIN. 7/16" WOOD STRUCTURAL SHEATHING MIN. LENGTH OF PER TABLE R MIN. (2) 1/2" DIAMETER ANCHOR BOLTS INSTALLED PER R WITH 2"x2"x3/16" PLATE WASHER MIN. DOUBLE 2x4 POST (KING AND JACK STUD). NUMBER OF JACK STUDS PER TABLES R502.5(1) & (2). INTERMITTENT BRACED WALL REQUIRED ADJACENT OPENING FOR SINGLE PORTAL FRAME FRONT ELEVATION For SI: 1 inch = 25.4 mm, 1 foot = 305 mm ANCHOR BOLTS PER SECTION R SECTION MINIMUM WALL STUD FRAMING NOMINAL SIZE AND GRADE FIGURE R METHOD PFG: PORTAL FRAME AT GARAGE DOOR OPENINGS IN SEISMIC DESIGN CATEGORIES A, B AND C TABLE R TENSION STRAP CAPACITY REQUIRED FOR RESISTING WIND PRESSURES PERPENDICULAR TO METHOD PFH, PFG AND CS-PF S MAXIMUM PONY WALL HEIGHT (ft) MAXIMUM TOTAL WALL HEIGHT (ft) MAXIMUM OPENING WIDTH (ft) TENSION STRAP CAPACITY REQUIRED (lb) a Basic Wind Speed (mph) Exposure B Exposure C DR x4 No. 2 Grade DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR DR 2x6 Stud Grade DR DR DR DR DR DR DR DR DR For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 lb = 4.45 N DR = design required a. Strap shall be installed in accordance with manufacturer s recommendations. Revised Wall Bracing Provisions 2012 NC Residential Code 12

18 EXTENT OF HEADER WITH DOUBLE PORTAL FRAMES (TWO S) EXTENT OF HEADER WITH SINGLE PORTAL FRAME (ONE ) PONY WALL HEIGHT 2' -18' FINISHED WIDTH OF OPENING FOR SINGLE OR DOUBLE PORTAL TENSION STRAP PER TABLE (ON OPPOSITE SIDE OF SHEATHING) 12' MAX TOTAL WALL HEIGHT 10' MAX. HEIGHT MIN. 3" X 11-1/4" NET HEADER STEEL HEADER PROHIBITED FASTEN SHEATHING TO HEADER WITH 8D COMMON OR GALVANIZED BOX NAILS IN 3" GRID PATTERN AS SHOWN HEADER TO JACK-STUD STRAP PER TABLE R ON BOTH SIDES OF OPENING OPPOSITE SIDE OF SHEATHING MIN. DOUBLE 2X4 FRAMING COVERED WITH MIN. 7/16" THICK WOOD STRUCTURAL SHEATHING WITH 8D COMMON OR GALVANIZED BOX NAILS AT 3" O.C. IN ALL FRAMING (STUDS, BLOCKING, AND SILLS) TYP. MIN. LENGTH OF PER TABLE R BRACED WALL LINE CONTINUOUSLY SHEATHED WITH WOOD STRUCTURAL S IF NEEDED SPLICE EDGES SHALL OCCUR AND BE ATTACHED TO COMMON BLOCKING WITHIN 24" OF WALL MID- HEIGHT. ONE ROW OF 3" O.C. NAILING IS REQUIRED IN EACH EDGE. TYPICAL PORTAL FRAME CONSTRUCTION FASTEN TOP PLATE TO HEADER WITH TWO ROWS OF 16D SINKER NAILS AT 3" O.C. TYP. MIN. 7/16" WOOD STRUCTURAL SHEATHING MIN. (2) 1/2" DIAMETER ANCHOR BOLTS INSTALLED PER R WITH 2"x2"x3/16" PLATE WASHER MIN. DOUBLE 2x4 POST (KING AND JACK STUD). NUMBER OF JACK STUDS PER TABLES R502.5(1) & (2). OVER CONCRETE OR MASONRY BLOCK FOUNDATION ANCHOR BOLTS PER SECTION R WOOD STRUCTURAL SHEATHING TO TOP OF BAND OR RIM JOIST NAIL SOLE PLATE TO JOIST PER TABLE R602.3(1) (2) FRAMING ANCHORS APPLIED ACROSS SHEATHING JOINT WITH A CAPACITY OF 670 LBS IN THE HORIZONTAL AND VERTICAL DIRECTIONS NAIL SOLE PLATE TO JOIST PER TABLE R602.3(1) WOOD STRUCTURAL SHEATHING OVER APPROVED BAND OR RIM JOIST OVER RAISED WOOD FLOOR - FRAMING ANCHOR OPTION (WHEN PORTAL SHEATHING DOES NOT LAP OVER BAND OR RIM JOIST) APPROVED BAND OR RIM JOIST MIN. OVERLAP 9-1/4" WOOD STRUCTURAL SHEATHING CONTINUOUS OVER BAND OR RIM JOIST NAIL SOLE PLATE TO JOIST PER TABLE R602.3(1) ATTACH SHEATHING TO BAND OR RIM JOIST WITH 8D COMMON NAILS AT 3" O.C. TOP AND BOTTOM NAIL SOLE PLATE TO JOIST PER TABLE R602.3(1) OVER RAISED WOOD FLOOR - OVERLAP OPTION (WHEN PORTAL SHEATHING LAPS OVER BAND OR RIM BOARD) FRONT ELEVATION For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 lb = 4.45 N WOOD STRUCTURAL SHEATHING OVER APPROVED BAND OR RIM JOIST SECTION APPROVED BAND OR RIM JOIST FIGURE R METHOD CS-PF: CONTINUOUSLY SHEATHED PORTAL FRAME CONSTRUCTION R Ends of braced wall lines with continuous sheathing. Each end of a braced wall line with continuous sheathing shall be in accordance with one of the end conditions shown in Figure R Revised Wall Bracing Provisions 2012 NC Residential Code 13

19 CONTINUOUSLY SHEATHED BRACED WALL LINE CONTINUOUSLY SHEATHED BRACED WALL LINE RETURN AT END OF BRACED WALL LINE END CONDITION 1 HOLD- DOWN DEVICE AT END OF BRACED WALL LINE END CONDITION 2 CONTINUOUSLY SHEATHED BRACED WALL LINE CONTINUOUSLY SHEATHED BRACED WALL LINE 48" MINIMUM AT END OF BRACED WALL LINE END CONDITION 3 CONTINUOUSLY SHEATHED BRACED WALL LINE 10' MAX. Return panel: RETURN D* *SEE REQUIREMENTS 10' MAX. END CONDITION 4 REQUIREMENTS FIRST BRACED WALL 24" for braced wall lines sheathed with wood structural panels 32" for braced wall lines sheathed with structural fiberboard HOLD-DOWN DEVICE END CONDITION 5 FIRST BRACED WALL For SI: 1 inch = 25.4 mm, 1 foot = 305 mm, 1 lb = 4.45 N Distance D: Hold-down device: 24" for braced wall lines sheathed with wood structural panels 32" for braced wall lines sheathed with structural fiberboard 800 lbs capacity fastened to the edge of the braced wall panel closest to the corner and to the foundation or floor framing below FIGURE R END CONDITIONS FOR BRACED WALL LINES WITH CONTINUOUS SHEATHING R Braced wall panel connections. Braced wall panels shall be connected to floor framing or foundations as follows: 1. 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 (1). Fastening of top and bottom wall plates to framing, rim joist, band joist and/or blocking shall be in accordance with Table R602.3(1). 2. 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 (2). Where a parallel framing member cannot be located directly above and below the panel, full-depth blocking at 16 inch (406 mm) spacing shall be provided between the parallel framing members to each side of the braced wall panel in accordance with Figure R (2). Fastening of blocking and wall plates shall be in accordance with Table R602.3(1) and Figure R (2). 3. Connections of braced wall panels to concrete or masonry shall be in accordance with Section R Revised Wall Bracing Provisions 2012 NC Residential Code 14

20 CONTINUOUS RIM OR BAND JOIST FULL HEIGHT BLOCKING CONTINUOUS ALONG LENGTH OF PERPENDICULAR FRAMING 6" O.C. ALONG 6" O.C. ALONG 16" O.C. ALONG 16" O.C. ALONG PERPENDICULAR FRAMING CONTINUOUS RIM OR BAND JOIST FULL HEIGHT BLOCKING CONTINUOUS ALONG LENGTH OF For SI: 1 inch = 25.4 mm FIGURE R (1) CONNECTION WHEN PERPENDICULAR TO FLOOR/CEILING FRAMING CONTINUOUS RIM OR END JOIST ADDITIONAL FRAMING MEMBER DIRECTLY ABOVE FULL HEIGHT 16" O.C. ALONG 6" O.C. ALONG 6" O.C. ALONG TOE NAIL 3-8d NAILS AT EACH BLOCKING MEMBER 16" O.C. ALONG 16" O.C. ALONG 3-16d AT EACH BLOCKING MEMBER CONTINUOUS RIM OR END JOIST ADDITIONAL FRAMING MEMBER DIRECTLY BELOW 2-16d NAILS EACH SIDE FULL HEIGHT 16" O.C. ALONG BRACED WALL For SI: 1 inch = 25.4 mm FIGURE R (2) CONNECTION WHEN PARALLEL TO FLOOR/CEILING FRAMING 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 Revised Wall Bracing Provisions 2012 NC Residential Code 15