Did my engineer just break my heart? (vented attic assembly)
Ok, I’m just going to go ahead and vent. Actually, I can’t, and that’s what’s making me heated, literally.
I’ve loved my engineer, loved! Why, well, first and foremost, he’s an engineer, what the hell is there not to love.
I’m a licensed builder in Southern California, working on a small 1,000 sqr foot modern Craftsmen style new construction project. All the structural details look fantastic on our plans, but in reviewing, the typical rafter to wall connection detail (attached) had me pause. I sent him an email immediately with attachments for venting at the eave (specifically on top of the blocking between the rafters at the roof sheathing), along with an example of a detail at the ridge providing for a cor-a-vent style static exhaust system. Here I thought – easy enough, we’re going to simply add in these details and be on our way to vented high performance.
Well, what do I know, I’m just a builder, not an engineer.
He shot both down. Saying that a) the blocking at the eaves is a critical part of the assembly b) the 2 x 1 1/2″ gaps in the plywood at the ridge would compromise the diaphragm and structural integrity (see detail attached – we called for a Simpson tie on each rafter.
I protested and said “why not cut the 1 1/2″ gaps at the ridge, then add the straps” — seemed like a solid idea. But to no avail.
Seems like I have to bore holes in the blocking and add a bug screen; then maybe use a solar fan somewhere in the middle of the roof near the ridge.
Anyone have a similar issue ? Any solutions out there?
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