How to Self-Install Metal Roofing

Buy panels to fit your roof; panels come in lengths from 6 to 20 feet and typically in panels 26 inches wide designed to cover 24 inches of roof with a 2-inch overlap on each panel. Measure the roof with a tape measure and try to fit panels to those dimensions. Be aware that longer panels will require extra help and even 6- or 8-foot panels can be difficult for one person to handle.

Make sure the roof decking is solid and lay roofing paper over it from side to side, starting at the bottom. Overlap sheets of paper at least 6 inches. Fasten it to the decking with a construction stapler and use a utility knife or shears to cut it as necessary.

Place the first panel at the bottom of one edge of the roof, even with the sides and bottom of the decking. Fasten it with 1-inch galvanized or aluminum screws, depending on the type of panel, driven into the second corrugation valley from the edge of the roof. Use a screw gun to drive screws with plastic or rubber washers under the head. Drive the screws firmly, but not so hard as to compress or break the washer, which seals the screw hole from moisture.

Place screws about every 18 inches across and up the panel. Leave the last valley open. Overlap the second panel by one ridge and one valley and drive screws through both panels to secure them to the roof and to each other. Add panels across the width of the bottom of the roof.

Start a second row of panels, if necessary, with a half panel. Use tin snips to cut a panel in half lengthwise. Put the cut side of the panel on the interior of the roof and overlap that panel on the bottom row by at least 6 inches. Drive screws through both panels along the lower edge of the second panel. Install panels up to the peak of the roof or a juncture with a wall on a single-slope roof.

Cover the top of the roof with peak caps or special top cap flashing, made to conform to the specific corrugations. Get this material from the same supplier as the panels. Install edge caps or similar seals along the side and bottom edges. Match this to the type of panel. Some manufacturers use fiberglass filler strips for edging; others use specially formed metal edges.