How To Apply A Metal Roof Over Osb

Most metal shingles will be attached to the roof using metal shingle.

How to apply a metal roof over osb.

This is by far the most common way to install a metal roof. Lay the starter row of metal shingles at the drip edge and affix to the roof with metal roofing nails. Space the screws about 12 in 30 cm apart down the entire piece of metal. I guess at 14x16 you won t be towing this one but the wind still blows and osb does not have adequate holding power to resist the wind trying to rip the metal roof sheeting off.

In order to avoid a hump at the transition from two layers of materials to one the notation on the building plans advises to lower the roof purlins in these areas by 7 16. Oriented strand board commonly referred to as osb is a type of engineered lumber similar to particle board formed by adding adhesives and then compressing layers of wood strands. A potentially easier option is to use purlins on top of the rafters rather than framing between the rafters. How to apply metal roofing over plywood step 1.

Work up from the initial row starting at the lower corner in a diagonal pattern staggering the shingles to prevent gaps. In the case above the shear forces in the last 12 foot bay at each end of the roof have had osb placed between the roof purlins and the steel roofing. A homeowner recently wrote and asked me the following regarding osb roof decking. Hello there i am about to have a contractor put on a metal roof on my house in central florida he is going to removing the old shingles then placing a moisture barrier on top of the osb then the metal roofing i have seen many other contractor use 1 x3 strips on top the barrier then metal which i think is stronger because the 1 x 3 strip are screwed directly to the rafters every 24 36.

That s common for metal roofing. As long as the plywood under the shingle roof is in good condition this way can provide many benefits. Case in point one of our recent clients in colorado has hired a building contractor to erect his building. 3 install 1x4 purlins down over the shingles before installing the metal roof the third way to install a metal roof over shingles is by applying 1x4 purlins over the shingle roof.

Sweep the plywood clean of all dirt and debris with a push broom. Repair any rotted sections of plywood before installing the metal panels. Use your neoprene washer head screws to secure the metal to the sheathing. 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.

Osb is widely used as roof decking material. This particular contractor happens to admit to sheathing over 90 percent of all of the post frame buildings he has put up in 7 16 osb oriented strand board beneath the steel roofing and siding. Take care the first piece is aligned precisely perpendicular square to the edge. Inspect the plywood for damaged areas.