Installing Steel Roofing Over Plywood

16 gauge purlins to secure the metal roof panels.

Installing steel roofing over plywood.

The plywood should be clean and free of raised nail heads to provide a uniform deck structure for the metal. But it seems the condensation will affect the 2x4 strapping. 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. 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.

The two main types of substrates used with metal roofing systems are open framing and solid substrates composite or plywood. Although you can install corrugated metal roofing over shingles for the best foundation it is recommended that all the old roofing be removed. Yes metal roofs are placed directly to the plywood over icynene insulated roof sheathing thats how i always had it done and warranteed. Energy efficient and available in a variety of colors that will.

For many applications a layer of plywood underneath your metal roofing is an unnecessary expense. Noise is usually not a factor if you are installing a steel roof over asphalt. 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. Work at a comfortable steady pace trying not to rip up or carry off too much old roofing at once.

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. Install waterproof felt over the plywood to add protection against moisture. Steel roofing can be costly but it is a lifetime investment.

The installation should be reviewed with the metal roofing manufacturer. On top of this underlayment goes a slip which protects the material from tearing as the metal roof expands and contracts with changing weather. As long as the plywood under the shingle roof is in good condition this way can provide many benefits. 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.