Roof Sheathing Over Old

Because the plywood roof sheathing under the shingles has become brittle and weak he plans to install new plywood as well as new shingles.

Roof sheathing over old.

Sheathing works with other components of the roof as well. Over time shiplap fir wood resin dissipates causing the boards to shrink crack form knot holes and become extremely brittle. The keyword here is solid it used to be standard to use shiplap 1 boards tongue groove or other boards for the roof deck. I have it under contract to resheath and reroof.

Walking on the roof feels very spongy. Today a shiplap roof is usually 60 years old. The roof is sheathed with either 3 8 or 7 16 inch plywood. Roof shingles are to be replaced.

Attic ventilation comprises of a poorly installed ridge vent with no soffit vents. It is now warped and wavy. But can he simply install new plywood over the old. Roof sheathing provides an area where the surface material can be attached but it also helps keep the trusses and or rafters properly spaced.

Sheathing is installed over multiple trusses rafters so it essentially turns them into one cohesive unit instead of individual structural members. Roof sheathing the material nailed to your trusses or rafters to which your roofing is attached is your roof s workhorse. There does not appear to be any roof leaks but from poking at the sheathing from below there appears to be dry rot. The contractor has asked if it is possible to leave the old sheathing in place and install the new 5 8 inch sheathing over the top of it.

As roofing contractors in seattle we are often asked why do we need plywood over our old solid sheathing. The anchor of the system that keeps. Housing and urban development hud rehab guide. Question 1 which is preferable from a quality perspective cost is secondary.

It is in your best interest to apply solid sheathing over the existing shiplap for your roofing system to securely fasten to. This guide was developed and edited for old homes from original material in the u s.