Installing Steel Roofing Over Plywood

On top of this underlayment goes a slip which protects the material from tearing as the metal roof expands and contracts with changing weather.

Installing steel roofing over plywood.

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. Noise is usually not a factor if you are installing a steel roof over asphalt. But it seems the condensation will affect the 2x4 strapping. The two main types of substrates used with metal roofing systems are open framing and solid substrates composite or plywood.

For many applications a layer of plywood underneath your metal roofing is an unnecessary expense. The installation should be reviewed with the metal roofing manufacturer. This is by far the most common way to install a metal roof. Install waterproof felt over the plywood to add protection against moisture.

The open frame substrate uses wood or metal framing members such as bar joists or min. 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. As long as the plywood under the shingle roof is in good condition this way can provide many benefits. The plywood should be clean and free of raised nail heads to provide a uniform deck structure for the metal.

Although you can install corrugated metal roofing over shingles for the best foundation it is recommended that all the old roofing be removed. 16 gauge purlins to secure the metal roof panels. Yes metal roofs are placed directly to the plywood over icynene insulated roof sheathing thats how i always had it done and warranteed. 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.

Ensure that the plywood deck is strong enough to withstand the added weight of the metal panels. Energy efficient and available in a variety of colors that will. Work at a comfortable steady pace trying not to rip up or carry off too much old roofing at once. Steel roofing can be costly but it is a lifetime investment.