Building codes say you can put a second layer of shingles over the first layer but it s better to strip off the old shingles and start with a clean slate.
Roof strip and replywood.
Loads will vary with the pitch of the roof.
Get 2020 roofing underlayment price options and installation cost ranges.
There s anecdotal evidence that new shingles installed over old shingles won t last as long as a single layered roof most manufacturers offer the same warranty for both methods.
Find roof panel closure strips at lowe s today.
Input project size product quality and labor type to get roofing underlayment material pricing and installation cost estimates.
When used for roofing plywood panels are covered and protected by a variety of building materials that keep the elements at bay including roof felt underlayment flashing and shingles.
Free online roofing underlayment cost guide breaks down fair prices in your area.
In some cases local building codes will limit the available options most do not allow more than two roof coverings on a building.
Most roofs will be sheathed in plywood at least 3 8 inch thick.
The most common uses for plywood include support for floors walls roofs and garages in residential construction.