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Roof Flashing: The Key to Preventing Roof Leaks

Our durable roof flashing moves water quickly off your roof to prevent damage from water and ice buildup.

Proper metal roof flashings are used to keep water out of your home by sealing the roof surface to the house. They also keep water, ice, and snow away from your roof.

There are three different areas that require proper roof flashing treatment.

Drip Edge

After your old roof is torn off and damaged or rotten sheathing is repaired, the first element to be installed is the drip edge. The drip edge is installed on the perimeter of the roof along the eaves and provides an added level of waterproofing.

The drip edge:

  • Deflects water into your eavestroughs, rather than between the eavestroughs and fascia, where it can damage the fascia board
  • Helps protect the roof deck from unnecessary exposure to water
  • Covers any gaps between the roof deck and the fascia boards caused by movement due to weather changes
  • Adds support to the first row of shingles

The drip edge should be rugged and resistant to corrosion to ensure a long life.

It is essential that all these flashings be replaced when reroofing: chimneys, skylights, plumbing stacks, vents, and valleys. More about roof flashing.

We will let you know the condition of all roof flashing when we inspect your roof and point out any potential problems or required repairs.

Valley Flashing

Valleys in your roof deserve special attention as they naturally deal with more water run-off than the rest of the roof.

There are two types of valley construction – closed valleys and open valleys. Closed valleys have shingles covering the valley, while open valleys have a gap between the shingles on either side, with metal in the valley. Both are permitted by the Alberta Building Code but we do not recommend, nor do we use, closed valleys. Open valleys provide superior and more durable protection.

The Alberta Building Code requires that all valleys have flashing, either underlayment or metal.  We prefer to use both for added protection, and we also use starter shingles on both sides of all valleys to increase protection against the wind.

Roof Penetrations

Roof flashing is also vital in these areas:

  • Chimneys
  • Skylights
  • Roof/wall intersections
  • Other roof penetrations such as vents or plumbing stacks

Learn more about roof flashing here.