The manufacturers recommend screws in the valley 3 per perling and shorter screws spaced 18 to 24 inches depends on the manufacturer on the ridges.
Roofing screws in the ridge or flat.
Screws in the flat nails on the ridge.
Quite often the screws are over tightened or under tightened and when this happens it creates leak points.
Your roof will have thousands of screw holes.
The main cause of a leaking roof on a diy metal roofing installation is incorrectly fastening the screws.
Make sure to screw through closures.
Sharp point metal to wood siding screws.
As the screws are driven the washer presses against the metal roofing to form a water proof seal.
I strap all roofs with nothing less than 2 4 to help lock that roof in place.
Attach ridge cap to rib of roof panel with screws on every rib along both sides of rib.
Metal moves some heat cold expansion and makes a bigger hole in metal for a leak.
Valid arguments can be made for both preferences.
The idea being that the longer screws in the valley hold the sheet down and the shorter screws on the ridges keep the wind from picking up the sheet.
Ridge cap should be end lapped 6 inches at each end.
Screwing or fastening down a metal roof is one of the easiest parts of a metal roofing installation but it s also the most problematic.
On the ridges can distort the metal.
Having done several metal roofs since then i would say if you are an amateur screw on the flat with 1 1 2 screws.
Make sure and not get them too tight don t squish the rubber gasket just nice and snug.
4 6 out of 5 stars 10.
Place large tab closure between the ridge cap and the roof panels.