How To Install Metal Roofing Over Osb
Begin on the left side of the roof working to the right.
How to install metal roofing over osb. Next use 1 inch nails to secure some metal edging to the perimeter of the roof. Before you install metal roofing repair any damage to the wood under the shingles. April 3 2017 filed under. Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
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. Work toward the ridge. Case in point one of our recent clients in colorado has hired a building contractor to erect his building. And for any exposed fasteners try to avoid over tightening them.
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. Try to space the screws about 12 inches apart down the entire piece of metal. Moreover try to ensure that the screws are all aligned evenly. A potentially easier option is to use purlins on top of the rafters rather than framing between the rafters.
Install the first metal panel on the low end of the roof square to the eave. 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. 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 line. Secure the metal panel to the deck by drilling 1 1 2 inch galvanized metal screws through the peak of the rib in 12 inch to 16 inch intervals.
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. Metal roofing screws need to go into framing. You will use metal roofing screws to secure the metal panels to the sheathing. Overlap the edge of the roof by 1 inch.