Installing Steel Roofing Over Plywood

But it seems the condensation will affect the 2x4 strapping.

Installing steel roofing over plywood. In reading online it seems wise to install a vapor barrier over the plywood to prevent condensation from getting adsorbed into the plywood from the steel roof. The open frame substrate uses wood or metal framing members such as bar joists or min. 3 install 1 4 purlins down over the shingles before installing the metal roof the third way to install a metal roof over shingles is by applying 1 4 purlins over the shingle roof. For many applications a layer of plywood underneath your metal roofing is an unnecessary expense.

Galvanized steel which is created by using a soft layer of zinc to protect the inner layers is the most common type of steel roofing. Although you can install corrugated metal roofing over shingles for the best foundation it is recommended that all the old roofing be removed. Steel roofing can be costly but it is a lifetime investment. 16 gauge purlins to secure the metal roof panels.

I was planning on putting plywood over the rafters and cross the rafters with a 2 x4 every 16 to secure the metal roof to. Noise is usually not a factor if you are installing a steel roof over asphalt. Install waterproof felt over the plywood to add protection against moisture. This is by far the most common way to install a metal roof.

To secure it measure it roll it out over the plywood cut it to the dimensions of the roof with a roofing or utility knife and finally hammer it securely to the plywood with 1 2 inch roofing nails. Work at a comfortable steady pace trying not to rip up or carry off too much old roofing at once. On top of this underlayment goes a slip which protects the material from tearing as the metal roof expands and contracts with changing weather. The plywood should be clean and free of raised nail heads to provide a uniform deck structure for the metal.

The installation should be reviewed with the metal roofing manufacturer. Ensure that the plywood deck is strong enough to withstand the added weight of the metal panels. The two main types of substrates used with metal roofing systems are open framing and solid substrates composite or plywood. Energy efficient and available in a variety of colors that will.