Roof Plywood Delamination

I had my roof sheathing replaced a year ago.

Roof plywood delamination.

Plywood is a sandwich of thin veneers glued together with heat. One of the implications of high moisture levels from either condensation or leakage is delamination of plywood sheathing. The more layers the better. This is sometimes accompanied by buckling.

Although delamination can be caused by several factors separation often occurs as a result of improper manufacturing processes. If the environment is humid moisture can get trapped between the membrane and insulation. Like blisters delamination can come from improper installation in inclement weather. Roof decking plywood delamination if you have a home twenty five years or older you may want to consider the condition of the plywood.

High moisture levels break down the glue in the plywood and allow the plies to delaminate. This winter i went up. It was plywood and had delaminated. Delaminations commonly affect single ply and fully adhered roofs.

Blows are a. The causes of plywood delamination plywood anatomy. Even the best manufacturing equipment. Particularly on the roof.

Between the years of around 1964 to 1975 homes being built saw the installation of what was first generation fire retardant plywood. Panel type roof sheathing may lift off the rafters in a regular pattern. When the membrane and insulation separate.