Wood-Frame Failures During Construction

[SASteve]

Looking to start a discussion on failures of wood-frame buildings that occur during construction. Have heard of a few incidents in Canada recently. The first appears to have been due to improper temporary diagonal bracing on the truss chords:

http://www.lfpress.com/2017/10/13/i...t-down-middlesex-mutuals-new-home-in-ilderton

The second failure is less clear; these townhomes were nearly complete and failure appears to have initiated in the walls:

http://regina.ctvnews.ca/overnight-winds-blow-down-houses-trees-and-scatter-debris-1.3637531

Does anybody have knowledge of these failures or similar cases? Who is usually found to be at-fault in insurance claims? Is there a design wind speed used in specification of temporary bracing?

 

[jayrod12]

I would say, 90% of the wood failures during construction are improper temporary bracing, whether it's trusses or walls. Otherwise there's not much typically available to go wrong. The construction loads are typically much lighter than the design loading and therefore overloading of the gravity members rarely happens (in fact, I don't know if I've ever seen a failure in a gravity member during construction).

 

[jayrod12]

As for the Regina one, the pictures don't give a clear enough picture, but I wonder if this wasn't constructed with only a half height concrete wall, then a small wood knee wall up to the underside of main floor. Everytime I see a residence constructed that way I get bad feelings as they are just creating a knuckle at the top of the concrete wall.