- Q.Do you nail metal roof
panels through the ridges or in the flats?
A. Corrugated roofing is always
nailed through the ridges. Metal roofing panels
with wide flats, however, are usually nailed or
screwed through the flats to form a solid
connection to the sheathing or purlins. Follow the
manufacturer’s guidelines, and always use
fasteners with rubber washers.