How to Install Chimney or
Swamp Cooler Flashing

How to Flash Ducting and Chimneys

The main goal of installing flashing is to get all the water that falls onto the roof to end up running down the shingles and not finding its way into your home via ducts or any other roof penetrations.

Most roof leaks occur at a vulnerable spot such as a chimney, vent, duct, or skylight. We’ll show you how to successfully install step flashing to protect your roof from leaks.

You’ll want to use step flashing to allow the water to cascade down the roof without any chance of encountering an unprotected spot. You’ll also need to account for wind, rain, and snow when installing your flashing. Don’t skip important steps because the natural flow of water wouldn’t be an issue. With the right conditions, almost nowhere on your roof is protected from the elements. 

Following the slope of the roof, install several steps of flashing starting from the lower end of the duct or chimney and moving upward, creating a layered barrier of flashing and shingles, as indicated in the video.

When you’re installing the flashing along the topmost edge of the duct or chimney, make sure you use a single piece material. Using smaller shingles will give water a chance to leak into your roof structure because it won’t be able to run down the roof due to the duct blocking it’s path. 

Depending on the state of your duct or chimney, you’ll want to attach the upper, unsecured portion of the flashing to the duct via screws and silicone to be extra sure that your roof stays water tight for years to come!

Happy Roofing!

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There are dozens of signs that your roof may be reaching the end of its life: water damage, leaking, discoloration, brittle shingles, cracked tiles, and rusted metal, to name a few. The best way to know for sure whether or not it’s time to replace your roof is to have a professional come and conduct a roof inspection. If you suspect that it might be time to get your roof replaced, give us a call, and we’ll come out for a free inspection! Trust The Roof Guys for your roof replacement needs.
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