How To Install Tin Roofing Over Shingles. They also tend to be loyal to roofing materials that they trust and will know exactly how to safely and effectively install it over your old roof. The industry standard for underlayment is often thought of as felt paper (tar paper) but there are also many newer synthetic underlayments that are designed to work well with metal roofing.
Venting—the eaves to vent the roof, holes are cut in the old roof above the soffit, which pulls air through the soffit vents underneath. This is what it looks like when you install a steel shingle roof system over an existing asphalt shingle roof. Cool outside air travels under the shingles to the vented ridge, pulling out moisture and heat.
How much does a metal roof cost?
On flat, even roofs, you can place the metal roofing directly on top. Install roofing on both sides of a ridge and cut them so they butt closely together but do not overlap. These slats of wood run perpendicular to the metal roofing itself. Step by step metal roof installation.