3
votes
1answer
372 views

How much sag on a roof is acceptable?

I have minor sagging of my roof plywood, 3/8" thick, placed on trusses 24" apart. Is there an amount of sag that is technically okay? I could not find anything on the APA website. I am not worried ...
4
votes
2answers
933 views

Can you use plywood as roofing?

I've seen buildings where plywood was used as both wall sheathing and siding. T-111 is commonly used this way, for example. Would it work to do the same thing on a roof? I assume it wouldn't last ...
6
votes
2answers
2k views

How is installing roof sheathing horizontally stronger than vertically?

Prompted by a comment in this answer: What is better for a roof, plywood or OSB? Why is it stronger to install roof sheathing horizontally? Yes, it ties in more rafters, but in what manner is that ...
13
votes
6answers
10k views

What is better for a roof, plywood or OSB?

While watching the builders next door do their thing, I became curious with their technique to install plywood on edges neighboring the next townhouse, and OSB for the rest (which for these narrow ...
3
votes
1answer
3k views

How do I nail plywood to flat roof framing?

I am putting some 3/4 plywood on top of 2x6 framing joists on my flat garage roof. The framing is spaced 16oc. I figured that I place 4x8 plywood sheets in such way that their short edge will be ...