Installing A Metal Roof Directly To Plywood

How to apply metal roofing over plywood step 1.

Installing a metal roof directly to plywood.

Be sure the larger edge is laid so that the small edge of the next panel will overlap it. Take care the first piece is aligned precisely perpendicular square to the edge. 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. Sweep the plywood clean of all dirt and debris with a push broom.

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. 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. Epdm roofing installation faq.

But it seems the condensation will affect the 2x4 strapping. Remove all unused vents pipes and protrusions. 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. 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 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. Use the reinforced solitex mento plus roof underlayment on top of your rafters. Inspect the plywood for damaged areas. Do need to rack the house with sheathing on walls or cross bracing.

If a proper roof inspection isn t done the 1x4 s could be installed over rotten plywood which means the screws could pull out. Repair any rotted sections of plywood before installing the metal panels. Always begin working at the point with the longest peak to eave distance. 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.

Install the roofing screws vertically along each rib in the panel. 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. To watch the entire series from the beginning click here. In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building.