How To Install Vent Pipe Flashing On Flat Existing Roof

This great video presentation shows you how to seal a pipe on a flat roof to avoid water ingress and completely waterproof a flat roofing installation.

How to install vent pipe flashing on flat existing roof.

The neck of the flashing should fit snugly around the pipe. Put one nail in the bottom edge with a dab of caulk under it to seal the. Use roofing nails to install the l shaped flashing flush with the roof and wall then cover it with roofing cement and reattach the roofer s felt. Slide the new flashing over the vent pipe and under the shingles above the pipe.

Add a large bead of caulk in a half moon shape around the flashing and put the shingles back in place. To make the installation easier you can turn the flashing as you lower it in place. Center the pipe in the flashing and push the flexible front corners up or down so that the flashing pipe is parallel to the vent pipe. Roofing nails per side photo 2.

I ve used this repair on several roofs over the years. Now that the old flashing is gone you can slide the new flashing over the pipe vent and maneuver it under the shingles above the pipe. Rubber vent flashing automatically adjusts to any pitch lift the vent enough to spread caulk under the sides but not the bottom edge then nail with three 1 1 4 in. In simplest terms a new vent pipe boot flashing is slid over the top of the existing one and the top edge of the pan is lapped beneath the overlying shingle course.

Use one roofing nail in each corner of the flashing to secure it to the roof. Finally reattach all shingles removed in the process. Install flashing on existing roof to extend the lifespan of your roof.