Chimney Waterproofing
Keep water out without sealing moisture in
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4.9 · 3,412 Google reviews
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CSIA & NFPA certified
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1-year workmanship warranty
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Same-day PDF report
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40 years sweeping chimneys
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3,412 verified Google reviews
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4.9 average rating
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CSIA-certified crew
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NFPA 211 compliant
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Licensed in 6 states
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100% background-checked technicians
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Free estimates
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40 years sweeping chimneys
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3,412 verified Google reviews
●
4.9 average rating
●
CSIA-certified crew
●
NFPA 211 compliant
●
Licensed in 6 states
●
100% background-checked technicians
●
Free estimates
●
40 years sweeping chimneys
●
3,412 verified Google reviews
●
4.9 average rating
●
CSIA-certified crew
●
NFPA 211 compliant
●
Licensed in 6 states
●
100% background-checked technicians
●
Free estimates
●
40 years sweeping chimneys
●
3,412 verified Google reviews
●
4.9 average rating
●
CSIA-certified crew
●
NFPA 211 compliant
●
Licensed in 6 states
●
100% background-checked technicians
●
Free estimates
Pricing, before you commit
Want an estimate before booking?
Waterproofing is quoted after the masonry is assessed, because sealing failed joints achieves nothing. Use our free Inspection Cost Calculator to see what that assessment costs, in under 30 seconds. No email, no callback, no surprise fees.
Estimate preview
Live
waterproofing
Quoted after masonry assessment
Inspection (credited)
−$49
Typical job
Two-coat application
Final price quoted in writing before any work.
The craft, done properly
WHAT CHIMNEY WATERPROOFING IS
Waterproofing is the application of a penetrating sealer to the exposed brick and mortar above your roofline. Brick is porous by design — it absorbs water and releases it again as vapour. A penetrating vapor-permeable sealer soaks into that pore structure and repels liquid water while still letting the masonry breathe outward. That distinction is the entire job, and getting it wrong causes more damage than doing nothing.
Brown Chimney uses vapor-permeable sealers only, applied in two coats to full coverage. We never use film-forming sealers: a surface film blocks moisture already inside the masonry from escaping, and trapped water destroys brick faster than rain ever will. One rule comes before all of it — if your mortar joints have deteriorated, tuckpointing comes first. Sealer cannot fix a failing joint, and we'll say so before taking money for it.
The storm a sealed chimney doesn't mind
The Work
What waterproofing actually does.
Almost every expensive chimney repair started as absorbed water. Brick takes moisture in, and when that water freezes, heats, or carries salts, it works the masonry apart from inside — spalling faces, efflorescence, deteriorating joints. Sealing the surface stops liquid water at the door while leaving the exit open for vapour, which is why the vapor-permeable requirement isn't a preference.
Timing and order matter more than product. Sealer goes on masonry that is sound, clean, and dry — never over failing joints, never over damp brick, never as a substitute for repair. It's cheapest and most effective right after repointing, while the joints are fresh and we're already on the roof. If the crown is cracked as well, that gets addressed first too — crown repair closes the largest water entry point on the structure, and sealing the walls below it while the top is still open just delays the same leak.
Related reading: does a chimney still need waterproofing if you barely use it — the short answer is that weather doesn't care how often you light a fire.
When to book
When is chimney waterproofing worth doing?
Waterproofing is preventive, not corrective — it protects sound masonry rather than repairing failed masonry. These are the situations where it earns its cost.
If the joints are already failing or brick faces are spalling through, sealing won't hold — repair comes first. A $49 inspection tells you which stage you're at, and the fee credits toward the work.
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Brick needs to breathe. Seal it with the wrong product and you've trapped the water inside — we've replaced more brick ruined by bad sealer than by bad weather.
Company Owner
The Brown Chimney Standard
Built to last. Backed in writing.
1-year workmanship warranty
Every piece of structural labor we perform is covered for a full year — in writing, not in promises.
Same crew, every visit
You get a W-2 technician you'll recognize next year — not a rotating cast of subcontractors.
Photos before, during, after
Your report documents the work at every stage. You see exactly what was done and why.
Price fixed before we start
Measured on site, quoted in writing, approved by you — then the work begins. Never the other way around.
What to expect
What happens during chimney waterproofing?
Waterproofing is a single visit on sound, dry masonry. Two coats are applied to full coverage — a one-coat shortcut is the kind that shows up as failure a few seasons later.
01
Masonry condition check
Sealer doesn't fix failing joints. If the mortar is deteriorated, tuckpointing comes first — and we'll tell you that before taking money for a coating that can't hold.
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02
Cleaning & drying the masonry
Masonry has to be clean and dry before anything is applied. Debris, efflorescence, and loose material are cleared from every exposed face above the roofline.
03
First coat application
A penetrating vapor-permeable sealer goes on all exposed brick and mortar above the roofline. Never film-forming — a sealed skin traps moisture inside the masonry and destroys brick faster than rain ever would.
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Second coat
A second coat is applied over the first. Two coats is the standard here; a single coat is the shortcut that shows up as failure a few seasons later.
05
Inspection & photo report
Coverage is checked across every face, the finished work photographed for your report, and backed by the 1-year workmanship warranty on all labor performed.
For transparency
What this visit doesn't cover.
Tuckpointing, if the joints have deteriorated — that comes first and is quoted separately
Crown sealing, which uses a different product and is priced as its own line
Masonry below the roofline, which sits in a different exposure and is assessed separately
FAQs
Common questions about chimney waterproofing
Does chimney waterproofing actually work?
On sound masonry, yes. A penetrating vapor-permeable sealer stops liquid water entering the brick while still letting absorbed moisture escape as vapour. What it cannot do is repair failed joints or cracked brick — Brown Chimney assesses the masonry first and says so when repair is what's needed.
What's the difference between vapor-permeable and film-forming sealers?
A vapor-permeable sealer penetrates the brick and repels water while letting moisture escape outward. A film-forming sealer coats the surface and traps moisture inside the masonry, where it does more damage than rain. Brown Chimney uses vapor-permeable products only, without exception.
Should I waterproof before or after tuckpointing?
After, always. Sealing deteriorated joints achieves nothing — the water simply enters through the failed mortar. Repointing comes first, then the sealer goes on fresh, sound masonry. Doing both in the same visit is the cheapest sequence, since the access is already set up.
How often does a chimney need resealing?
It depends on exposure, orientation, and the product used. Brown Chimney checks the condition of previously sealed masonry during annual inspections, so resealing is flagged in your photo report when it's genuinely due rather than sold on a fixed schedule.
Is waterproofing worth it on a chimney I never use?
Weather doesn't care whether you light fires. An unused chimney takes the same rain, sun, and temperature cycling as a working one, and absorbs water the same way. If the masonry is sound, sealing it is one of the cheapest ways to keep it that way.
Related Services
Often paired with waterproofing.
A safer hearth — for 2026
Sealed properly — or repaired first.
Every Brown Chimney waterproofing job starts with a masonry assessment, uses vapor-permeable sealer in two coats, and is backed by a 1-year workmanship warranty. Book online or call 1-888-666-0002.