How to Connect a Metal Roof to an Asphalt Roof

Whether you're installing an addition to an existing building or simply re-roofing part of it, connecting a metal roof to asphalt shingles poses some problems.
Installing a new roof can be time-consuming, but is a fairly simple operation.Installing a new roof can be time-consuming, but is a fairly simple operation.
Most metal roof paneling has ridges running down its length, while shingles are fairly flat, resulting in a series of gaps at the juncture between the two. To successfully connect the two types of roofing, you'll need to seal the gaps to prevent rainwater or small creatures from finding their way in.

Step 1

Remove the staples from the lowest row of shingles, allowing them to be lifted up.

Step 2

Staple tar paper to the part of the roof on which you're installing the metal paneling. Install the metal panels as recommended by the manufacturer, starting in the lower downwind corner of the roof. Work up the roof one panel at a time until you reach the shingles.

Step 3

Lift the lowest row of shingles and slide the topmost metal panel slightly underneath the shingles, securing it to the roof as with the other panels. Continue installing the metal roof, starting with the column of panels just upwind of the first, until the entire tar papered area is covered. Install the metal roofing trim as instructed.

Step 4

Slide an outside foam closure strip under the bottom row of shingles. This will fill the gaps between the ridged metal panels and the flat underside of the shingles. Run a bead of roofing sealant over the closure strip to secure it in place.

Things You Will Need

  • Tar paper
  • Staple gun
  • Metal roofing panels and trim
  • Drill and screws
  • Outside foam closure strips
  • Roofing sealant

About the Author

Mark Keller has been writing everything from short stories to political commentary over the course of the past decade. He has written professionally since 2009 with articles appearing on LibertyMaven.com, Penguinsightings.org, Pepidemic.com and various other websites. He is a theater major at Hillsdale College in Michigan.