First because the frame is screwed directly to the rafters and the interlocked shingles are screwed to the frame the roof can withstand winds of up to 120 mph without damage.
How to install metal roof shingles.
A benefit to doing it this way is that you can see if there is any rotten plywood that needs to be replaced before installing the new roof.
You should start your metal shingles installation with half a shingle or in accordance with your metal shingles installation manual which should be system specific starting from the left of the starter flashing or gable.
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.
This framework has three big advantages.
Nail the drip edge in place using your hammer and roofing nails.
Starter shingles should be laid at the drip edge nailed down with roofing nails.
Next lay the shingles working from the lower corner of the roof upward.
Install metal roofing sheets.
1 remove the shingles before installing the metal roof the first way to install a metal roof over shingles is by completely removing the old shingles before installing the new metal roof.
Experts recommend that you work diagonally and raising each row of shingles gradually.
Always install flashing around a chimney and other valleys where two roof planes meet as these areas are more prone to leaks if not protected.
Install the roofing screws vertically along each rib in the panel.
Install new flashing metal flashing is often called drip edge along the bottom of the roof near your gutters.
Fasten the shingles to the roof using the nail clips designed specifically for metal shingles.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
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.
Better steel shingle systems like the one shown install over a framework of 2x2s.
Metal roofing sheets have to be installed one at a time.