Installing A Metal Roof Directly To Plywood

Epdm roofing installation faq.

Installing a metal roof directly to plywood. 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. Always begin working at the point with the longest peak to eave distance. Place the first screw. Inspect the plywood for damaged areas.

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. In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building. Sweep the plywood clean of all dirt and debris with a push broom. Repair any rotted sections of plywood before installing the metal panels.

Add purlins on top of this for venting and drainage then add horizontal purlins to mount the metal roof to. When using plywood nail it directly to the purlins and screw the metal roofing panels through the plywood into the purlins as instructed by the manufacturer. Add the metal 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.

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. To watch the entire series from the beginning click here. Do need to rack the house with sheathing on walls or cross bracing. How to apply metal roofing over plywood step 1.

Remove all unused vents pipes and protrusions. If a proper roof inspection isn t done the 1x4 s could be installed over rotten plywood which means the screws could pull out. 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. 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.

Be sure the larger edge is laid so that the small edge of the next panel will overlap it. On top of this underlayment goes a slip which protects the material from tearing as the metal roof expands and contracts with changing weather. Take care the first piece is aligned precisely perpendicular square to the edge. 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.