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While a brick chimney looks sturdy, masonry is highly porous and naturally absorbs water. Over time, prolonged moisture exposure degrades the brick and mortar, threatening the structural integrity of both your chimney and your home. Safeguard your property from water intrusion and expensive repairs with our expert waterproofing services in the greater White Plains and Long Island area.
Chimney waterproofing protects your masonry from one of its biggest enemies – water. Our process starts with a careful evaluation and ends with a breathable, water-resistant barrier that helps your chimney stand up to the elements season after season.
There are several products that have been developed specifically for waterproofing masonry chimneys, but not every product will do the job well. You will need to find products that are 100% vapor permeable, which will allow the chimney to breathe, while simultaneously blocking water from entering your chimney.
Here at Alpine, we use ChimneySaver water repellents, which are trusted by chimney professionals everywhere.
Reduces Water Penetration by 99.9%
ChimneySaver dramatically reduces moisture absorption by creating an invisible, breathable barrier across the entire masonry surface.
Freeze/Thaw Protection
ChimneySaver prevents water from getting trapped inside the masonry, effectively reducing the risk of freeze-thaw damage.
Mildew & Fungus Resistant
ChimneySaver's water-repellent formula helps keep your masonry dry, which in turn inhibits the growth of harmful vegetation.
Doesn't Affect Chimney Appearance
Unlike many sealers that leave a glossy, wet-look finish or visibly alter the color and texture of the masonry, ChimneySaver goes on completely clear and dries to a natural, breathable finish.
While DIY waterproofing products are widely available at hardware stores, chimney waterproofing is always best handled by a trained professional.
One of the most common mistakes homeowners make is selecting the wrong type of sealant - many over-the-counter products are film-forming and non-breathable, which means they seal moisture inside the masonry rather than keeping it out. Over time, this trapped moisture expands and contracts with temperature changes, accelerating cracking, spalling, and mortar deterioration far faster than if nothing had been applied at all.
A professional chimney technician will begin with a thorough inspection to identify all active moisture pathways before any product is ever applied. They will then use a professional-grade, 100% vapor-permeable waterproofing treatment that is specifically formulated for masonry chimneys. This ensures water is blocked from entering while still allowing any moisture already inside the chimney to escape as vapor.
Masonry (including brick, stone, and mortar) is a naturally porous material that inherently absorbs small amounts of moisture from rain, humidity, and condensation. Under normal conditions, this moisture evaporates back out as water vapor without causing damage. This ongoing cycle of absorption and vapor release is why chimney experts often say masonry needs to "breathe."
When you apply a non-breathable, film-forming sealant or paint to the exterior of your chimney, you effectively trap any moisture that is already inside the masonry with no way to escape. As temperatures fluctuate - especially through freeze/thaw cycles in colder climates - that trapped moisture expands and contracts, building up enormous internal pressure. The result is accelerated spalling, where the face of bricks flake and pop off, as well as crumbling mortar joints and deep structural cracks.
A vapor-permeable waterproofing product resolves this conflict entirely: it creates a hydrophobic barrier on the surface of the masonry that repels liquid water from penetrating inward, while still maintaining a large enough molecular structure to allow water vapor already inside to migrate outward and evaporate.
No - painting a chimney is one of the most damaging things you can do in an attempt to waterproof it, and it is a mistake we see frequently.
Standard exterior paints, elastomeric coatings, and most waterproofing sprays found at general hardware stores are film-forming products. They sit on the surface of the masonry and create a physical barrier that blocks both liquid water and water vapor from moving through. While this might sound effective, it completely ignores the porous nature of masonry and the moisture that is inevitably already present within the chimney structure.
Once that moisture has no escape route, it becomes trapped. During cold weather, the trapped water freezes and expands, exerting pressure upward and causing severe spalling, deep structural cracks, and rapid mortar joint failure.
Repairing spalled brickwork and rebuilding deteriorated mortar is far more expensive than proper waterproofing would have been. The correct approach is to use a professional-grade, 100% vapor-permeable waterproofing treatment.
The freeze/thaw cycle is one of the most destructive natural forces acting on your chimney, and it is the primary reason why water intrusion is considered the number one enemy of masonry structures. Here is how it works:
• Brick and mortar are porous materials that absorb water during rain, snow, or periods of high humidity.
• When temperatures drop below freezing, that absorbed water turns to ice.
• Water expands in volume as it freezes, and within the confined spaces of masonry pores and micro-cracks, this expansion generates enormous internal pressure.
• This pressure forces existing cracks to widen and creates new fractures throughout the brick and mortar.
• When temperatures rise again, the ice melts and the water either evaporates or is absorbed deeper into the masonry - only to freeze again the next night or the next cold snap.
Over the course of a single winter, a chimney can experience dozens or even hundreds of these freeze/thaw cycles. The cumulative effect is progressive and visible: bricks begin to spall (their faces flake and chip away), mortar joints crumble and fall out, and eventually large structural cracks can develop that compromise the integrity of the entire chimney.
Proper waterproofing with a vapor-permeable sealant dramatically reduces how much water the masonry absorbs in the first place, limiting the amount of water available to freeze inside the structure and significantly extending the life of your chimney.
We prioritize safety on every job, and we continuously invest in training and education to stay on top of industry standards.
We hold memberships and affiliations with the NCSG, NY State Chimney Sweep Guild, NFPA, and BBB.
Chimney sweeping, masonry repairs, gutter cleaning, dryer vent care - we handle it all so you don't have to coordinate multiple contractors.
Camera inspections are only offered when actually needed, and we'll never push services that you don't actually need.
We're not a franchise - just a local team that treats your home like their own and answers the phone 24/7.
I was getting water in my basement in the heavy rain. Alpine Chimney came to seal my chimney. They were polite and professional. They knew exactly what the problem was. Pricing is competitive with local chimney companies.
Matthew L.
GoogleThe work was executed quickly and effectively and they had all parts on the van. They went above and beyond sealing and painting over some rust/water stains. Very friendly and courteous. Cannot recommend them enough.
Armonk Resident
GoogleNot only did they do a thorough job, but they also conducted a roof inspection and alerted me to some moss that needed attention on the masonry. They took care of everything seamlessly. Their professionalism and attention to detail were outstanding.
Matt Oates
GoogleWhile waterproofing my two chimneys, Alpine was very accommodating and sealed some cracks on the chimney per my request. They even sealed an unrelated roof leak for me. We had a few heavy rains and Hurricane Henri, I am very happy to report that my basement was dry.
Sheng-I Doong
GoogleWe serve homeowners and businesses across Westchester, Putnam, and Suffolk Counties.
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Schedule your professional chimney waterproofing service today to better protect your home against costly water damage. We serve Westchester, Putnam, and Suffolk Counties - let us give your masonry the protective seal it needs to stand strong for years.
From waterproofing to chase cover installation, our leak prevention services keep your system in tip-top shape.