Install metal panels or shingles 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.
How to install metal roofing on shingles.
If you don t know how to cut metal roofing panels you can warp them or damage the protective coating that prevents rust.
Install the roofing screws vertically along each rib in the panel.
If you want to install steel over asphalt your best choice for installing metal roofing is to use a steel shingle system like the one shown instead of the more common and more expensive standing seam steel.
Experts recommend that you work diagonally and raising each row of shingles gradually.
Metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it.
It doesn t matter if the air space is a half inch or six inches because the condensation factor will remain the same.
Anatomy of a steel roof.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
This is what it looks like when you install a steel shingle roof system over an existing asphalt shingle roof.
In a standing seam roof long single panels run vertically all the way from the eave to the ridge.
Put the steel down directly on a vapor barrier.
Codes vary so call your local building department to know how to install metal roofing over shingles properly code wise.
Metal roof over shingles condensation.
Metal roofing is much more difficult to install than asphalt shingles.