by Jerry Peck - Codeman on Wed May 04, 2011 4:54 pm
Hi Marc,
No shear wall needed there that I can see.
Yes, the fire-resistance rated wall separating the townhouses is required to go to either: a) the underside of the roof sheathing and then roof sheathing either be protected by 5/8 inch gypsum board or the roof sheathing could be fire-retardant treated; or b) the fire-resistance rated wall would need to extend a minimum of 18 inches above the roof sheathing.
There should be NO communication between the attics of the two "separate" townhouses.
Also, I'm not even sure that roof framing is suitable for the two "separate" townhouses as, if the fire-resistance rated wall were there, one structure should be able to burn down without taking the adjacent structure (the structure on the other side of the fire-resistance rated wall) down with it - looks to me as though there is a main beam/girder toward the right of the photo which runs from one townhouse to the other, provided that masonry wall is the wall between the two townhouses.
Jerry Peck - CodeMan
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Construction Litigation Consultant - Retired
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