Never heard of gluing roof sheathing. No problem with double nailing. Just make sure the ply is the specified thickness.

I just assumed since they glued the floor sheathing. Thanks!

they're offering us a credit to keep. What would be a fair credit? We won't find out their offer until the morning. It's a 3000sqft 2 story hip roof with 2 gables.

Not likely they applied any adhesive to the trusses before installing OSB. I would not expect a huge performance difference in OSB vs. veneer plywood except that fasteners tend to hold better in veneer plywood.

Why did the framers order the wood instead of the GC?? Sounds like that GC is doing as little as possible.

Personally from my perspective they would be changing it.

For me, the more important issues are the thickness of the OSB and the wind speeds of the region. If the project is on the coast or another high wind area and the OSB is 5/8" or thicker, I see no practical advantage in replacing it with plywood. Nail pullout in plywood is superior for 1/2" thickness but I don't recommend 1/2" roof sheathing of any kind.

To me the primary advantage of plywood is that its edges shrink back to the original thickness after getting wet but that can be dealt with by using Advantech or another treated OSB or covering it before it can get wet which I assume has already happened.

I can't think of a reason to glue roof sheathing but perhaps its for wind resistance. If it is glued, I would not attempt to remove it.

I'm curious what others think about adding a layer of 1/2" plywood over the OSB. I imagine the hardest part would be marking the nailing pattern but easier than removing the OSB. But I would first want to know the wind condition, sheathing thickness and type of nail used.

We're in NW Chicago. GC told them to replace it on the first call. Carpenter came back and asked if we'd accept a credit instead so he extended the offer to us. I'll ask about thickness. No one told me the sheathing was glued. I know subfloors are so I incorrectly assumed roofs would be too.

I'll find out out about thickness and whether they used advantech or treated the cut edges. This was also my main concern on OSB. I'm probably going to have them pull it. We'll be there at least 20 years so I don't want to make concessions for a couple bucks.

I'll second that. That way, you'll get a better roof than you bargained for in the first place. And the framers are not spending hours messing with the OSB and possibly damaging the trusses, then having to re-roof.

I am with JDS and Worthy.

We are in IL and often we specify 5/8" OSB. I'd add synthetic underlayment instead felt paper and the Ice and Water dam membrane at valleys, ridges, flashed areas and all overhangs.

it's 5/8"osb. We had ice and water shield already at all valleys ridges and for the bottom 3 feet of every roof line. They're offering us $2,500 credit to keep the OSB. we're taking it. Thanks everyone for the input.

I would add Ice & Water Shield on the rest of the roof. Roofs don't leak just at valleys and eaves. Its cheap insurance and standard practice in northern New England.

What synthetic underlayment?

Owens Corning ProArmor™ Synthetic Roof Underlayment

GAF deck_armor

Something else?

Stapled underlayment of any kind will be punctured by thousands of nails so it is essentially a slip sheet for the shingles and protects the sheathing until they are installed. Ice & Water Shield is self-adhering and seals the nail holes. I've used it in lieu of loose underlayment for 30 years. Most contractors this far north insist on it now and you're as far north as I am.