Plywood Under Slate Roof

Today we hang the slates onto the roof deck with two nails.

Plywood under slate roof.

While it s not the main material for the roof itself roofing plywood is an important part in a roofing structure. A that the use of roof decking material other than asphalt will raise the cost of the job sky high and. When a slate roof is installed properly no underlayment is necessary. For many applications a layer of plywood underneath your metal roofing is an unnecessary expense.

Metal roofing panels rated for architectural use attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturer s instructions and local building codes. When re using old slates a 1 5 inch hot dipped galvanized nail will do. Ideally the wood will last 150 years or long enough to support an average initial slate roof and replacement slate roof. Many years ago roof slates were hung on slating lath with a single wooden peg driven through a hole in the top center of the slate.

This is an example of a grossly inferior roof deck. It s so important that you have to arm yourself with knowledge and know everything there is to know so you ll know the best way to utilize it for your roof. The best thing that should be under a roofing slate is all natural hard solid wood. Unfortunately many roofers will tell you.

Plywood has not demonstrated the longevity of slate and should be avoided under any permanent roof i e. The best slate roof are always installed on solid lumber not plywood particle board osb or any glued substrate. When nailing new slates use 1 5 copper roofing nails. Osb and plywood come in thicknesses ranging from 5 16 to 3 4 inch and the thickness needed for a particular roof depends on several factors including rafter spacing expected load and roof design.

The right sheathing choice is individual plank boards.