Installing A Metal Roof Directly To Plywood

Repair any rotted sections of plywood before installing the metal panels.

Installing a metal roof directly to plywood.

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. Add purlins on top of this for venting and drainage then add horizontal purlins to mount the metal roof to. Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof. Sweep the plywood clean of all dirt and debris with a push broom.

Always begin working at the point with the longest peak to eave distance. To watch the entire series from the beginning click here. Place the first screw. Installing the metal roofing over 1x4 s allows the ability to also install additional insulation under the metal roof that can t be done the other two ways.

Remove all unused vents pipes and protrusions. On top of this underlayment goes a slip which protects the material from tearing as the metal roof expands and contracts with changing weather. Inspect the plywood for damaged areas. Take your first sheet of metal and place it on the roof so that it overhangs the edge at least 3 4 in 1 9 cm.

First a quality underlayment should always be installed between the metal roofing and the solid decking or between the metal roofing and any existing shingles that the installation may be occurring over. Use the reinforced solitex mento plus roof underlayment on top of your rafters. Install the roofing screws vertically along each rib in the panel. If a proper roof inspection isn t done the 1x4 s could be installed over rotten plywood which means the screws could pull out.

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. Take care the first piece is aligned precisely perpendicular square to the edge. Epdm roofing installation faq. How to apply metal roofing over plywood step 1.

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. Add the metal panels. In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building. But it seems the condensation will affect the 2x4 strapping.