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Chimney Crown Sealing in Seattle, WA
A sound crown sealed now stays sound. Flexible, breathable crown coat applied before cracks open. Free quote, price match plus 10-25% off.
- Free 2nd-opinion quotes
- Price match + 10–25% discount
- Same-day service often available
Request a Free Chimney Crown Sealing Quote
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Chimney crown sealing is maintenance, not repair. The crown is the concrete slab that closes off the top of a masonry chimney, and even a crown with no visible cracks is slowly drinking rain through its surface pores. Sealing it means cleaning that surface and applying a flexible, breathable crown sealant that sheds water while still letting trapped moisture escape as vapor. Done while the crown is still whole, it keeps the slab from ever reaching the crack-and-patch stage.
This page is about the preventive job on a crown that is in good shape. If your crown already has open cracks, a separated flue joint, or an old coating peeling off, you need crown repair, which fills the cracks first and then coats. If it is crumbling or was never a real poured slab, sealing it is wasted money and a crown rebuild (starting at $299) is the honest answer. We tell you which of the three you are looking at, with photos, on the free quote visit.
Sealing is usually a one-visit job, so same-day service is often available when the forecast cooperates. We serve Seattle, Tacoma, Everett and the road-accessible Puget Sound.
Symptoms
Signs you need chimney crown sealing
- The crown looks intact but turns dark and stays damp for a day or more after rain
- A faint chalky film comes off on your hand or a cloth from the crown surface
- Crown has never been coated and the chimney is more than a couple of decades old
- Tiny surface crazing you only notice up close, not open cracks
- A previous crown coat is thinning or dulling but has not lifted or peeled
- Light efflorescence starting on the top course of brick just under the crown
- You just had crown or masonry work done and want to protect the investment
Common causes
- Concrete is porous; an unsealed crown absorbs rain through its surface even without cracks
- Sun and rain slowly erode the cement paste at the surface, opening more pores each year
- Moss and leaf debris sitting on the crown keep it saturated for weeks at a time
- An old sealant that has reached the end of its life and no longer beads water
- Thermal cycling of the flue starts micro-cracking at the surface long before it shows
How It Works
Our chimney crown sealing process
Before we seal anything we confirm the crown qualifies. We tap the slab for hollow spots, check that it sits tight on the brick and overhangs it, look for any crack wider than a hairline, inspect the joint around the flue tile, and test whether the surface is still absorbing water. A solid, uncracked crown gets the sealing quote. A cracked one gets a crown repair quote instead, and a failing one gets a rebuild quote; we do not sell a coating onto a crown that needs more. The cap and flashing are checked on the same climb, and you receive photos of all of it.
Free quote and crown check
We verify the crown is sound and uncracked, confirm the flue joint is tight, and write a quote that says exactly which product and how many coats.
Clean the surface
Moss, dirt, loose paste and any old failing coating are removed so the sealant bonds to clean, dry concrete.
Mask and prepare
The flue tile, cap base and the top brick course are protected so the sealant goes only where it belongs, with the edge lapped over the drip line.
Apply the crown sealant
A flexible, breathable crown coat is brushed on in the number of coats the product specifies, working the edges and the flue perimeter carefully.
Cure and document
The coating cures in dry weather; we send you finished photos and note the date so you know when to have it checked again.
Options
Repair and service options
Crown sealing comes in a few forms depending on the crown and the rest of the chimney top:
- Seal only: the basic preventive coat on a sound crown. The least expensive thing you can do for a chimney top, and the one most homeowners never hear about.
- Seal plus flue-joint detail: if the joint between flue tile and crown is tight but unsealed, we add a high-temperature flexible bead there, since it is the first place water finds its way in.
- Seal plus chimney waterproofing: the crown coat above and a breathable repellent on the brick below, done together so the whole exposed chimney sheds water.
- Seal as part of a maintenance plan: we check the coating at your annual inspection and re-apply only when it is due.
- Not a fit: cracked crowns go to crown repair; crumbling ones to a rebuild.
Every option is quoted free and in writing. If you already have a written quote for crown sealing, we give a free second opinion, match it, and take 10-25% off.
Pricing
What affects the price
- Crown surface area and number of flues passing through it
- How much cleaning or old-coating removal the surface needs first
- Whether the flue-joint bead is included
- Number of coats the chosen sealant calls for
- Adding brick waterproofing on the same visit
- Chimney height, roof pitch and access
Every chimney is different, so you get a written quote after we look at the system. Ask about our price match and free second-opinion quote.
Safety & Seattle Conditions
Safety considerations
Sealing a crown is a short job, but it happens at the highest point of your roof. Please do not go up to check whether your crown is damp or chalky; the free quote includes photos taken from the top. If you have noticed concrete flakes in the gutter, the crown is past the sealing stage and we will quote the right repair instead.
NFPA 211 recommends an annual chimney inspection. That visit is the natural time to look at the crown coating and decide whether it is still doing its job, which is how sealing stays cheap instead of turning into crown repair.
Seattle & Puget Sound conditions
The reason to seal a crown before it cracks is simple arithmetic. Sea-Tac's normal annual precipitation is 40.34 inches, with about 73% of it falling October through March, and Seattle averages roughly 150-156 days a year with measurable rain. An unsealed crown spends most of the wet season saturated, and with about 60 days a year touching 32F against winter lows averaging around 37F, that water freezes and thaws repeatedly; the Brick Industry Association notes that repeated freeze-thaw of saturated masonry is what produces cracking, crazing and spalling.
Western Washington moss spreads fastest October through April on slow-drying surfaces, and a mossy crown never gets the dry spell a bare one would. Clearing it is part of the sealing visit.
Our Work
Chimney Crown Sealing in action
Seal the crown while it is still sound
Call 206-453-2045 or send a photo of your chimney top. Free quote, free second opinion, price match plus 10-25% off. If you're not happy, we're not done.
☎ 206-453-2045 Request a QuoteQuestions
Chimney Crown Sealing FAQ
What is the difference between crown sealing and crown repair?
Sealing is preventive: the crown is sound and uncracked, and we coat it so it stays that way. Repair means the crown already has open cracks or a separated flue joint that have to be filled before any coating goes on. Same coating family, different starting point. If you are not sure which you need, the free quote settles it with photos.
Why seal a crown that is not leaking?
Because concrete absorbs water through its pores long before it cracks, and every wet winter moves it closer to cracking. A crown coat applied while the slab is whole costs a fraction of crown repair and far less than a rebuild. It is the same logic as painting wood siding before it rots rather than after.
Is the sealant breathable, and why does that matter?
Yes. We use crown sealants designed to shed liquid water while letting water vapor escape from the concrete. A non-breathable film traps moisture already inside the slab, and when that moisture freezes it can lift the film and damage the surface. Breathability is the difference between a coating that protects the crown and one that slowly harms it.
How often does chimney crown sealing need to be re-applied?
It depends on the product, sun exposure and how wet the chimney top stays, so we do not promise a fixed number of years. What we do is check the coating at your annual inspection, look for dulling, thinning or spots that no longer bead water, and re-apply only when it is actually due. We note the application date so the next check is easy.
Can you seal the crown in winter?
The surface must be dry and the temperature within the product's range, so winter is harder but not impossible. Dry windows do come through even in the wet season, and we schedule around the forecast. The ideal time is late spring through early fall, which is also when same-day service is most often available.
My crown already has a crack. Can you just seal over it?
No. A coating over an open crack bridges it for a season and then splits along the same line. The crack has to be opened slightly, cleaned and filled with a flexible compound first, and then the whole crown is coated. That is the crown repair service. We will quote that instead and tell you why.
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