Installing A Metal Roof Directly To Plywood

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.

Installing a metal roof directly to 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 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. Take care the first piece is aligned precisely perpendicular square to the edge.

Always begin working at the point with the longest peak to eave distance. Epdm roofing installation faq. 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. Add purlins on top of this for venting and drainage then add horizontal purlins to mount the metal roof to.

If a proper roof inspection isn t done the 1x4 s could be installed over rotten plywood which means the screws could pull out. 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. Be sure the larger edge is laid so that the small edge of the next panel will overlap it. Repair any rotted sections of plywood before installing the metal panels.

In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building. Place the first screw. Use the reinforced solitex mento plus roof underlayment on top of your rafters. Inspect the plywood for damaged areas.

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. Add the metal panels. 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. To watch the entire series from the beginning click here.

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. How to apply metal roofing over plywood step 1. Sweep the plywood clean of all dirt and debris with a push broom. Install the roofing screws vertically along each rib in the panel.