It s usually a peel and stick product that adheres directly to the roof deck.
2 layers of roof sheathing.
Plywood is layers of wood.
I think there are better ways to design an unvented roof for example by using rigid foam above the roof sheathing instead of closed cell spray foam on the underside of the roof sheathing.
Roof sheathing materials plywood.
It got nailed over 2 x 12 joists 24 o c.
I am replacing a roof right now built in 1982 and the 3 ply is delaminated pretty heavily.
Poor ventilation from a past roof along with 3 ply equals that delamination.
Water shield is the next roofing layer that creates a water proof barrier where ice or water can buildup near the roof eaves.
Wood shakes minimum 3 4 sheathing wood shakes nail type minimum length.
Can you double up plywood roof sheathing without inviting disaster 2000 sf of 1 2 cdx ply went on the roof before i had a chance to take a look at it and it is really sorry stuff.
And if you re still wondering what roof sheathing is and what materials are typically used read on and satisfy your curiosity.
Assuming your roofing contractor is using standard 36 wide 15 roofing felt double coverage means that each layer of felt put down across the roof laps 19 over the upper half of the previous course.
The first course starts with an extra 1 2 wide run.
Plywood used for roof decking is typically called sheathing and carries a grade stamp indicating its load and span ratings and other performance factors.
It s up to you.
Roof deck is the roofing material that sits on top of the roof trusses.
Should you sandwich roof sheathing between two impermeable layers.
Most building codes allow for two layers of asphalt shingles on a house so stripping off everything down to the plywood sheathing may not be your only choice.
So anywhere along the gable end that you can see the felt you ll see two layers.
Based on the pictures alone i don t know what to say.
On a 2 12 pitch roof.
Comes in standard 4 by 8 foot sheets is strong.
Most roof decking is made from sheets of plywood.
I m not a fan of spray foam.
Skinning over old sheathing does occur but i have never seen someone skin over plywood in that condition.