Our company, Miiller Construction, installs a lot of exposed-fastener metal roofs. Most of these are reroofs on homes, which we typically install over existing asphalt shingles. All of the commercially available metal roofing we can buy in our area is warranted for contact with asphalt, but we prefer to install 3 1/2-inch wood strapping first, securing it through the shingles to the sheathing with ring-shank nails. This gives us a firm base for the screws that hold down the roofing. Many of the older roofs in our area are decked with board sheathing. With a nail gun, it’s obvious when you miss a solid board, and you can just fire in another nail. But if you are screwing the roofing directly to the shingles and hit a dead space, you need to back the screw out and fill the hole with a grommeted stitch screw. All the extra holes in the metal makes for more risk than we care to take on. It also takes longer.

On the majority of roofs, we install 29-gauge panels, which are less expensive than heavier, 26-gauge panels. We explain to customers that the heavier-gauge material will withstand hail better, but most still opt for lighter-gauge material because of the cost. We can actually install 29-gauge metal (strapping, screws, and 29-gauge trims included) for less than we can install a good architectural shingle roof with a similar lifespan. Even at the lower cost, most of our clients see a metal roof as an upgrade over shingles. (We do price out heavier-gauge trims as an option, disclosing to customers that the lighter–gauge trim can oil-can easily, but most clients still go with the less expensive package.) The photos that follow here detail the key steps from a couple of roofing jobs that show our methods for a fast, quality installation.

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