ChimneySaver, is a masonry waterproofing product developed specifically for chimneys, has been used successfully by leading chimney professionals for nearly 20 years. It reduces water penetration into the masonry by 99.9%, according to ASTM tests conducted at the University of Wyoming.
It’s also 100% vapor permeable, which means it won’t trap water vapors that may pass through the bricks when the chimney is in use, unlike other products found in most hardware or home improvement stores. Beware of these cheaper product and sealers that actually seal water into the chimney and can actually cause and accelerate water damage .
Chimneys are built with common masonry products that are very porous and absorb a lot of water which can cause damage over time. It is a long, slow process, but over time it can do serious damage to the exterior and the unseen interior. Waterproofing is a cost-effective preventative maintenance measure to extend the life of the chimney system.
Because chimneys stand tall and unprotected, they’re exposed to the full brunt of the elements—rain, snow, and water vapor all take their toll, both inside and out. Especially in regions with harsh climates, like New England, regular exposure to moisture can make chimneys unsightly and even hazardous if left unchecked. That’s why it’s so important to protect your chimney with products specifically designed for long-lasting defense against water intrusion. Taking these steps now can help prevent expensive repairs and keep your chimney looking and functioning its best for years to come.
Common signs of water damage
- Efflorescence – exterior staining of the chimney , often white due to salts leaching out of the brick and mortar.
- Erosion – of bricks and mortar , where you see the masonry disintegrating and falling apart
- Spalled bricks – When bricks actually pop off faces and corners due to excessive water retention during the freeze/thaw cycles new England is famous for.
How Waterproofing Products Stand Up to Tough Weather
Waterproofing products like ChimneySaver aren’t just slapped together—they’re engineered to stand up to everything Mother Nature can throw at your chimney. In places like New England, where brutal winters follow muggy summers, chimneys endure endless cycles of rain, snow, deep freezes, and blazing sun.
The key? These protective coatings are developed to flex with temperature swings and form a tough, invisible barrier over masonry. They bond deep into the porous brick and mortar, repelling water without becoming brittle or trapping moisture. When properly applied, they accommodate the constant expansion, contraction, and movement that chimneys go through all year, so you don’t get cracks or flaking from thermal shock.
The result is a breathable shield that helps lock out water and salt, minimizing the risk of efflorescence, erosion, and freeze/thaw damage—all while letting your chimney “breathe” as it should. Thanks to these advances, waterproofing is now an essential line of defense in extending the life of chimneys exposed to harsh, shifting climates.
Why Chimney Crown Damage Matters
The chimney crown—the masonry “roof” at the very top of your chimney—plays a crucial role in keeping moisture out of the structure beneath it. When cracks form in the crown, water finds its way in. This can kick off a domino effect of trouble:
- Water leaks: Cracked crowns open the door for rain and snow to enter, leading to moisture pooling inside your chimney system.
- Internal deterioration: As moisture seeps down, it can damage both the inside and outside of your chimney, eroding mortar joints and causing hidden structural issues.
- Freeze-thaw havoc: In regions like New England, trapped water will freeze and expand, worsening those initial cracks and causing chunks of masonry to break off.
- Costly repairs: Left unchecked, this kind of damage can transform what might have been a simple fix into a full-scale chimney rebuild.
Routine maintenance and timely crown repairs go a long way in safeguarding your investment and preventing these headaches.
How Waterproofing Products Stand Up to Tough Weather
Waterproofing products like ChimneySaver aren’t just slapped together—they’re engineered to stand up to everything Mother Nature can throw at your chimney. In places like New England, where brutal winters follow muggy summers, chimneys endure endless cycles of rain, snow, deep freezes, and blazing sun.
The key? These protective coatings are developed to flex with temperature swings and form a tough, invisible barrier over masonry. They bond deep into the porous brick and mortar, repelling water without becoming brittle or trapping moisture. When properly applied, they accommodate the constant expansion, contraction, and movement that chimneys go through all year, so you don’t get cracks or flaking from thermal shock.
The result is a breathable shield that helps lock out water and salt, minimizing the risk of efflorescence, erosion, and freeze/thaw damage—all while letting your chimney “breathe” as it should. Thanks to these advances, waterproofing is now an essential line of defense in extending the life of chimneys exposed to harsh, shifting climates.














