Old Roof Decking

To prevent future mold growth remove the source of moisture causing it.

Old roof decking.

In older houses decking is typically made of lumber place perpendicular to rafters trusses. Plywooding over old roof deck one thing to consider when stripping off the old plywood is to remove and replace as you go. Roof decks on homes built before 1970 are often 1 8 fir pre plywood shiplap. In the 1950s plywood sheathing and particleboard became common and today most standard construction roofs use either half inch plywood or particleboard s big brother oriented strand board osb.

We knew that this old house had significant gaps in the wood p. Strip away the old you re permitted to have two layers of asphalt shingles on your roof so if there s only one in place now you can have a new layer installed right on top. It s important to know what kind of a substrate is underneath the wood shakes before removing. Older homes may very well have a different type of roof decking than newer structures.

Old houses with asphalt shingles usually had either tongue and groove boards or straight sided boards abutting. If you remove it all then reinstall you can have cracking and popping of the drywall ceiling. Until the 1940s exterior grade plywood was not available. Plank sheathing usually 1 6 or 1 8 was used as a roof deck before plywood.

Prevent future mold growth. The new plywood thickness should be. If there is a leak in the roof plumbing or windows the mold will reappear if the water is. In the first half of the 20th century roofs in missouri were built with wood shingles over planks spaced about 1 apart.

As long as the new plywood itself can span the distance and carry the roof wind seismic and snow loads for your region adding new ply over old is just fine. These decks rarely had roof insulation installed on them since energy was relatively cheap so typical construction might have called for a layer of rosin treated paper followed by two layers of bitumen impregnated roofing felt nailed followed by three more layers of 15 asphalt or pitch impregnated organic roofing felt mopped together.