How to Install the Trim for a Steel Roof

Steel roofs offer many advantages to homeowners, including longevity, resistance to mold and rotting, as well as easy maintenance. Steel is also recyclable, which makes it a sustainable building material. Steel roofing panels may have either hidden or visible fasteners, depending on the construction design. Do-it-yourselfers can save money by installing steel panels themselves, including the steel trim that is an important feature of the roof system. Trim may be installed at the ridges of the roof line, at valley points where two sections meet or at the lowest edge of the roof.

The trim is an important design element of a steel roof.

Step 1

Attach the drip edge trim recommended by the roofing manufacturer along the gutter line edge of the roof with screws and neoprene washers to prevent leakage from fastener holes. Ensure that any underlying roofing material, such as existing shingles, are covered so that the new edge allows rainwater to drip directly into the gutter.

Step 2

Lay in flashing for roof valleys where two roof surfaces meet and secure the piece on both sides with screws and neoprene washers as recommended in the manufacturer’s instruction manual. Apply butyl sealer tape to the edges to provide a tight fit.

Step 3

Install 4-by-6 inch rake trim along the gables of the house -- the raised edge of the roof line, not the lower gutter line. Insert screws at regular intervals at the top and sides spaced 24 inches apart.

Step 4

Attach the ridge cap to the peak of the roof line, according to the manufacturer’s directions. Generally, you must align the underlying steel sheets and fit the cap onto the peak. Insert screws with neoprene washers at every rib.

Step 5

Cut the ends of the ridge cap and turn down the edges with a pair of pliers, after installation, to create a neat, finished look for the roof line.

Step 6

Install transition trim at points where vertical wall surfaces meet the roof surface, such as the second story of the house or where the chimney meets the roof. Secure the trim with screws and neoprene washers.


  • Steel roof trim parts may have sharp edges that can cause injury. Wear heavy gloves when installing these parts.
  • Avoid installing panels or trim in windy conditions, which can cause flat steel sections to become airborne.