Flashing Repair & Installation

One of your chimney’s most important shields against water infiltration is its flashing, which is installed on all four sides where the chimney rises up out of the roof. When you’re trying to keep water out of anything — including a chimney — seams are potential weak points. So the seams between the chimney and the roof are of particular concern, and strong, properly- installed flashing is your best defense against leaks there.

Sometimes — particularly after bad weather events — portions of chimney flashing can be torn or damaged, or the high-performing caulk that’s used to seal some edges can pull off, giving water an opportunity to enter. Poorly-installed flashing, or flashing using rust- and corrosion-prone materials, can fail relatively quickly. Northeastern Masonry & Chimney technicians are extensively trained to provide the custom work required for proper flashing repair and installation and can advise you on the best material choices for your home.

Flashing Installation Explained

Proper flashing is constructed in layers, to provide optimum protection against water. A base layer of what’s called step flashing is installed first — L-shaped metal pieces are laid in with the roof shingles and up against the chimney. On top of the step flashing, we place counter flashing, which gets integrated with and installed into the mortar joints. Remaining seams are reinforced with caulk for even more protection.

With that layered construction, bolstered by caulk, water shouldn’t have any weak points to get into, and your chimney and home should have strong protection against water infiltration for years.

The materials used in flashing can differ, but the most commonly used are galvanized metal, stainless steel and copper. Galvanized metal will be the least expensive option, but it’s also the least durable, and often succumbs to rust and corrosion in relatively short order, making the installation of new flashing necessary. Stainless steel provides much longer-lasting protection.

Chimney with red brick in need of flashing repair on asphalt terra cotta colored roof, new flashing, down and chimney cap-blue sky.

Copper, while the most expensive choice, tends to appeal to people who want a particular look for their home. Copper flashing, aside from being highly durable, provides a bright pop when it’s new, and as it weathers, only gets more and more attractive.

Is your flashing in need of repairs, or do you need new chimney flashing installed? Northeastern Masonry & Chimney is here to help. Give us a call at 518-767-9315 or click here to make an appointment with our experienced, CSIA-certified technicians!


Did you know a smelly chimney could be caused by chimney leaks? Let us help you figure it out and fix it!