Commercial Roofing Construction Detail: Edge Metal Flashing (CT-01)

Hello Commercial Roofing Team, 

In this low-slope roof installation session, I will be coaching you and your team through the steps to install edge metal (Construction Detail CT-01). 

Proper installation of edge metal is a critical component for both wind and weather protection. Ensuring the edge metal is secured correctly and in a water-tight fashion is an often overlooked flashing detail. The edge metal will act as a shield against moisture infiltration from wind-driven rain and wind uplift.

When working on this detail, it is important to note that the membranes, Flintlastic® SA PlyBase and Flintlastic SA MidPly, are self-healing sheets. This means that, once you penetrate through the membranes, the sheet will “heal” around both the nail and the fasteners helping to provide a water-tight seal.

For successful installation, please follow the steps below, and then watch my quick demonstration video to see it in action. 

Let’s Get To Work!

1. A good edge detail starts in the field. Turn your field membrane over the outside edge a minimum of 2”, and nail off 4” on the center with metal cap nails. 

2. Make sure your fasteners near the edge of the roof start no closer than 6” in from the edge. You’ll be installing edge metal later, and you don’t want to create a stacked nailing scenario.

3. In a two-ply roof system, start with a half width of the base sheet to allow for a full width of the cap sheet without stacking side laps.

4. After the base sheet is in place, we require a 9” field-cut flashing strip of Flintlastic SA PlyBase or Flintlastic SA MidPly around the perimeter of the roof wherever edge metal is to be installed. 

5. Now apply an 1/8” bed of FlintBond® SBS-Modified Adhesive – Caulk or Trowel Grade – to either the undersurface of the metal, or the 9” strip. 

6. Then nail it in – staggering your nails 4” on center, two nails in any metal overlap.

7. Before applying your cap sheet, prime all metal surfaces. FlintPrime® Aerosol Asphalt Primer goes from spray to ready in about 30 minutes. Just make sure the surface is tacky and not wet before installing your Flintlastic SA Cap Sheet.

8. Last step is to get your cap sheet in place. Simply remove the release film, press down and roll in with a weighted roller to remove any entrapped air.