Wood Flexible Diaphragms
Wood Flexible Diaphragms
(OP)
thread507-388238: Wood Gable Roof Diaphragm
RFreund did you have a chance to discuss these items with Terry Malone.
I have been reviewing numerous structural drawings of multi-family construction in my area (Texas) that other consultants have put out and I have yet to see a single collector or drag strut called for. It is clear to me that WoodWorks (Terry Malone) is saying that they are required but I don't want to get fired from ever doing another multi-family wood frame project.
Has anyone seen a multi-family project in a wind dominant region where these items have been specified?
RFreund did you have a chance to discuss these items with Terry Malone.
I have been reviewing numerous structural drawings of multi-family construction in my area (Texas) that other consultants have put out and I have yet to see a single collector or drag strut called for. It is clear to me that WoodWorks (Terry Malone) is saying that they are required but I don't want to get fired from ever doing another multi-family wood frame project.
Has anyone seen a multi-family project in a wind dominant region where these items have been specified?






RE: Wood Flexible Diaphragms
I think it becomes more difficult since we tend to simplify plans because we know how they work in the field [some contractors are careless, and they don't even go by the plan] so i will say that we erroneously not provide a floor sheathing pattern specifying the location of each plywood sheet and the nailing as well as the locations of collectors with the specified nailing pattern and such and such but what we would provide are the sections [specially when you're using floor trusses] that specify a shear design load and the proper connection to the shearwall [this is to be designed by the truss manufacturer].
RE: Wood Flexible Diaphragms
It'll get you shot in my area unfortunately. We're just starting to warm up to hold downs. Some places where it seems to be getting done:
1) British Columbia sort of.
2) RFreund seems to be doing it (IL/WI).
3) Mike20793 seems to be doing it.
I've no doubt that there are others, I just can't remember them.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Wood Flexible Diaphragms
RE: Wood Flexible Diaphragms
RE: Wood Flexible Diaphragms
We typically have trusses perpendicular to the corridor walls so they could easily transfer the axial load across but how would they know to increase the diaphragm nailing unless you specify that it is a boundary element? Besides calling out each of the drag struts I assume you could have a typical detail that specified for all trusses in-line with a shearwall to have boundary nailing, but we all know this would never get done.
Another situation, in the longitudinal direction we typically only use the corridor walls as shear walls. If there is not a wall inside the units that closely lines up with the corridor wall then would a drag strut not also be required in this situation to drag the load to the corridor walls? The drag strut would typically be perpendicular to our floor framing so it would require that they add drag trusses or blocking between the trusses.
RE: Wood Flexible Diaphragms
Edit: In the rare event that shear walls line up across the corridor, I still use a collector to tie them together. And by collector I mean joist or blocking and a strap. The coil straps can be cut to length.
RE: Wood Flexible Diaphragms
You don't mean outrigger in the steel and concrete building sense do you? Just that you can use the little bitty walls around the exterior between openings?
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.