Understanding the 2012 IRC Brace Wall Methods in

Understanding the 2012 IRC Brace Wall Methods in section R 602. 10

R 602. 10. 1 Braced Wall Lines (BWL’s) R 602. 10. 1. 1– Length of Braced Wall Line Defines Distance Between the end as; -Establishes the concept of the “imaginary line” used to establish the location of the Braced wall Line (BWL) -At intersections with a perpendicular BWL -At angled BWL -At exterior wall -Plans must clearly indicate the location of the BWL’s for proper assessment R 602. 10. 1. 2 – Offsets along BWL No more than 4’ from the designated BWL location No more than 4’ for interior walls used as BWL’s

R 602. 10. 1. 3 – Spacing of BWL’s -Using table R 602. 1. 3 for wind condition 85 mph to < 110 - not more than 60” -Intermediate BWL’s through the interior shall be permitted R 602. 10. 2. 2 - Locations of Braced Wall Panels -Within 10’ from each end of BWL -20’ between measured from edge to edge R 602. 10. 2. 3 --BWL’s less than 16’ shall have two panels of any qualified length or one 48” or more. - Greater than 16’ needs to have a minimum of two BWP’s R 602. 10. 3 - Sub-paragraph 1 directs you to use two tables, one using Wind speed and the other is the adjustment factor table.

Sample house- as shown on plan Find the required length of bracing for BWL 3 Givens-90 mph wind (2012 IRC) -Exposure C -One story -Eave -to-ridge height 10’ -Walls 12’ 30’ 20’ 40’

Begin your Calculations #1 - Choose your requirements Table R 602. 10. 3(1) -Spacing(Between BWL’s) -Method of bracing WSP (wood structural panels) = Required minimum length of BWP is 5. 5’

#2 Adjustment Factors Exposure category -one story – condition “C”- Adj. Factor= 1. 2 Roof eave -to-ridge height- roof only- 10’=1. 0 Wall height Adjustment- 12’= 1. 10 Number of BWL- 3=1. 30 Total required 5. 5’ x 1. 2 x 1. 0 x 1. 1 x 1. 3= 9. 44’ of required BWP Along that one BWL you will need 9. 44’ of bracing (Adjusted factor) Compare each BWL using this same Method and provide on the Plans.

Using Tables R 602. 10. 4, R 602. 10. 5 & R 602. 10. 7 Calculate the remainder of the house ; bracing methods, bracing methods minimum length with opening, short walls, hold downs, etc.

• Make sure to have all your Braced Wall Lines on the plan • Identify all Braced Wall Panels by method used and location along the BWL • Show hold down location for Alternate Brace Panels Contact your local jurisdiction if you have any questions