2 layers of 1/2 inch Plywood Mit ?

What would you all mark for a roof deck on a wind mit for 2 1/2" layers of ply and 8 D nailed every 6" or less.

Curious of your opinions.

It was permitted and passed.

what size nails were used?

8D ring shank

Why are there two layers and how did determine that? Was the first layer damaged?

I determined it by the length of some 8D nails and from pictures of the roofing job and deck measurements help support it. Very complete photos of the process. If it is not then I have been had but based on my experience I believe all I have told you to be the case. Original areas that were damaged were allegedly replaced and then covered. It was permitted and each inspection passed so I believe the city inspector knew what was going on. I think they did it that way because it was cheaper than tearing it all off and disposing of it and less material costs overall and now they feel they have a 1" deck attached every 6" or less with 8D nails.

I would guess that the original 1/2 decking failed or warped significantly, was this a tile roof, and instead of ripping it all off, they got an architect to certify the new work of installing the 1/2 inch which would be thicker than 19/32, at least if all the measurements were true, when they were done and they could still use the 8D nails.

I would mark it 8D, six inches. No SWR though…:frowning:

It is a flat roof and it did not look like much like much sheathing damage from the photos but I guess they wanted to strengthen it. Some areas were replaced with the same 1/2" the covered again.

In that case, it is probably on 24 oc studs and that is why they added another layer of decking.

I think I may have given SWR once and it was based on photos and paperwork both of which was sent with an explanation. Never heard weather it flew or not.

Mark what you observed!
** Let the powers determine.**

That was what I did. Just curious of the standard practices of the guru’s round here :slight_smile:

Mike, depending if it was nailed 6 or 12 inches in the field and the trusses being a max of 24" oc, the answer would be b or c since the wording on the form says a minimum thickness of 7/16" it does not state a maximum thickness. So if you can prove 2 layers of 7/16’ and 8d nails your answer must be b or c.
You don’t have to prove mean uplift because it gives you the option by stating “or”.