Level 1 sweep and inspection to the NFPA 211 annual standard - flue, crown, cap, and flashing checked and photographed
Chimney sweep logs do not sweep chimneys. They loosen some creosote - which then falls where a brush and vacuum still have to collect it.
Fast, Reliable Chimney Repair Across North Kensington
Chimney repair in North Kensington usually means one of three things: repointing deteriorating mortar joints, fixing flashing where the chimney meets the roof, or replacing a clay tile liner that was never sized right for a gas furnace. Most jobs here run between $400 and $2,800 depending on what the camera finds. Wendell Pike and his crew at Top Hat Chimney have worked these brick colonials and Cape Cods long enough to know what’s behind the cap before they climb the ladder. If you’re seeing water stains on the ceiling near the fireplace or noticing mortar crumbs on the roof, call (240) 716-5865 and we’ll give you an honest read.
Why Top Hat Chimney Is North Kensington’s Preferred Chimney Repair Company
Wendell started Top Hat Chimney in 1999 and has been inside more North Kensington flues than he can count. Homeowners here tend to appreciate that the person who answers the phone is the same person who shows up at the door, and the number quoted over the phone is the number on the invoice. No franchise playbook, no bait-and-switch. Just a local sweep who puts his name on the work and runs into you again at the farmers market on Howard Avenue.
Every job gets a camera inspection before any repair is recommended. Not because it’s fancy, but because you shouldn’t have to take anyone’s word on a $2,000 liner job. The footage and a plain-English verdict, every time, no exceptions. And every completed repair carries the 90-Day Done Right Promise in writing. If it’s not right, one call brings Wendell back. That’s the whole agreement.
North Kensington homeowners also get the same standing offers we’ve honored for years: $40 off any repair over $200, a free second opinion on any written estimate, no trip charge inside the county, and 10% off always for seniors and veterans. Call (240) 716-5865 and a live person picks up, twenty-four hours a day.
Our Chimney Repair Services in North Kensington
Mortar Repointing
The lime mortar in North Kensington’s 1940s and 1950s brick chimneys is now 60 to 80 years old. Freeze-thaw cycling across DC winters forces water into hairline joints, where it freezes, expands, and pops the mortar loose. Left alone, the joints wash out and bricks start to shift. Repointing means cutting out the failing mortar and packing in fresh, correctly matched mortar that moves with the brick instead of fighting it. On a typical North Kensington colonial, repointing a chimney stack runs $600-$1,800 depending on access and how much joint work is needed.

Spalling Brick Repair
Spalling is what happens when water gets inside a brick, freezes, and blows the face off. It shows up as flaking or crumbling brick faces, usually near the top of the chimney where water sits. In North Kensington we see it most on chimneys that lost their crown wash years ago and have been absorbing rain ever since. We cut out the damaged brick, replace it with matching units, and address the moisture source so the new brick doesn’t spall within a season. Spalling brick repair in North Kensington typically falls between $400 and $1,200 per affected section.

Chimney Waterproofing
Brick is porous. Add decades of DC humidity and repeated freeze-thaw stress, and you have a chimney that soaks up water like a sponge. Waterproofing with a vapor-permeable sealant like ChimneySaver lets the masonry breathe while keeping rain out. This is one of the smartest, least expensive repairs we do in North Kensington. For most homes off Connecticut Avenue or Plyers Mill Road, waterproofing runs $450-$900 and adds years to a chimney that would otherwise keep spalling and cracking.

Flashing Repair
Flashing failures at the roofline are common in North Kensington because the newer gas appliances show no smoke. With a wood fire, you’d notice a smoky smell or staining around the chimney. With gas, the first sign is often water on the ceiling or a dark stain spreading along the drywall, long after the leak began. We replace old or improperly stepped flashing with properly integrated step and counter flashing, sealed at every course. Expect flashing repair on a North Kensington Cape Cod or colonial to run $500-$1,400. This is one repair you don’t want to wait on; the leak only gets bigger.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Common Chimney Repair Problems We See in North Kensington Homes
- Oversized clay-tile flues on gas conversions: Most North Kensington homes built before 1970 had chimneys sized for coal or oil heat. When the house converted to gas, usually in the 1970s or 1980s, the original 8×8 or 8×12 clay flue stayed. Now it vents a small gas furnace poorly, the flue gas cools too fast, and acidic condensate eats the mortar joints from the inside. Montgomery County inspectors flag this as a code violation and a carbon monoxide hazard. Our Chimney Repair team sees this on nearly every gas-converted home in the area.
- Freeze-thaw crown cracking: Temperatures around North Kensington cross freezing dozens of times each winter. Water finds a hairline crack in the crown, freezes, and widens it. Within a few seasons, the top courses of brick start popping off. Crown repair or rebuild stops the cycle.
- Flashing failures that hide until the ceiling stains: Gas furnaces don’t produce visible smoke, so a flashing leak at the roofline goes unnoticed. By the time a homeowner calls us, the water has typically run down the interior framing and stained a ceiling or wall.
- Spalling and leaning on 60-80-year-old lime mortar: The original mortar in North Kensington’s mid-century chimneys was softer than modern Portland cement mixes. Once the crown fails and water saturates the stack, the mortar washes out, bricks loosen, and a slight lean develops. We’ve caught several chimneys before they became a structural problem.
Pricing for Chimney Repair in North Kensington, MD
Here are honest numbers for the North Kensington market. Mortar repointing runs $600-$1,800. Flashing repair runs $500-$1,400. Chimney waterproofing runs $450-$900. Spalling brick repair runs $400-$1,200 per section. A stainless steel liner install, when Montgomery County code requires one, typically lands between $1,800 and $3,200. Full chimney rebuilds from the roofline up start around $3,500 and go up from there depending on height, access, and brick matching. Every estimate is free, and the price you hear before we start is the price on the invoice. Call (240) 716-5865 for a specific quote on your chimney.
Trusted Brands We Service in North Kensington
When a repair calls for new components, we work with manufacturers whose parts we trust and can get quickly for North Kensington customers. DuraFlex stainless liners are our standard for gas-converted flues because they handle acidic condensate better than clay tile ever did. We also install and service HeatShield and Gelco products when a liner can be resurfaced rather than fully replaced. Having these parts on hand means less waiting on a chimney that’s leaking into your ceiling.
We Also Serve Cities Near North Kensington
Top Hat Chimney handles chimney repair throughout the surrounding area, including Rockville, North Potomac, Redland, and Travilah. If you’re nearby and need a second opinion on an estimate or a camera inspection before the heating season, call (240) 716-5865. We’re glad to come out. You can also learn more about our work across the region on our North Kensington page.
Serving North Kensington, MD - Our Local Coverage Area
We’re based in the North Kensington area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Chimney Repair in North Kensington
Because your chimney was almost certainly built for coal or oil heat, not gas. North Kensington’s 1940s-1960s brick colonials and Cape Cods came with oversized clay-tile flues, usually 8×8 or 8×12. A modern gas furnace produces cooler, wetter exhaust that condenses inside those large flues. The acidic condensate eats the mortar joints from the inside out, and Montgomery County inspectors flag the oversized liner as both a code violation and a carbon monoxide hazard. A camera inspection takes about an hour and gives you a definitive answer. Call (240) 716-5865 for a free estimate.
If the bricks are still sound and the chimney is plumb, tuckpointing is usually enough. We cut out the old lime mortar and pack in a fresh, compatible mix. If the bricks have spalled, the crown is gone, or the stack has started to lean, tuckpointing alone won’t fix the underlying problem. Wendell will show you the camera footage and tell you plainly whether it’s a repoint or a rebuild. No guesswork, no upsell. Call (240) 716-5865 to schedule an inspection.
Once a year, burn or no burn. Newer factory-built fireplaces have manufacturer-specific parts that wear out on their own schedule: refractory panels crack, gaskets compress, and chase tops rust. In North Kensington’s humid summers and freeze-thaw winters, the galvanized chase caps on prefabricated units corrode faster than you’d expect. A yearly inspection catches a $300 chase cover before it becomes a $3,000 interior water damage claim.
A Level 2 inspection uses a video camera to see the entire flue interior, including the sections hidden behind walls and above ceilings. That matters in North Kensington because so many homes have original clay tile liners that were never resized for gas. A standard sweep looks at what’s visible from the top. A Level 2 catches cracked tiles, missing mortar, oversized flues, and condensation damage behind the surface. After any fuel conversion or home sale, it’s the only way to know what’s actually going on inside. We always document with footage and walk you through it.
Yes. Montgomery County requires a license for chimney work, and the county follows NFPA 211, which sets the standard for liner sizing, clearances, and construction. When a chimney is repaired or an appliance is replaced, the work must comply with current code. Wendell carries a Maryland Home Improvement Commission license and puts the number on every estimate. If someone knocks on your door in North Kensington offering a cheap chimney repair without showing a license, send them on their way. Then call (240) 716-5865 and we’ll come take a look.
What North Kensington’s Older Homes Teach Us About Chimney Repair
North Kensington is a tightly packed mid-century subdivision corridor wedged between Kensington and Wheaton along Georgia Avenue. Most homes were built between the late 1930s and the early 1960s as brick or frame colonials and Cape Cods. Almost every one of them has at least one full masonry chimney with original clay tile liners that are now 60 to 80 years old. Those chimneys weren’t built for gas heat. They were built for coal, then oil. When the houses switched to gas in the 1970s and 1980s, the flues stayed the same size. So today, when we open up a chimney on a gas-converted North Kensington home, we expect to find an oversized liner that Montgomery County inspectors flag as both a code violation and a carbon monoxide hazard. It’s not a rare surprise. It’s the pattern.
On a brick colonial off Georgia Avenue, our crew pulled the rain cap and found the original 8×12 clay-tile flue venting a small gas furnace; a conversion done decades ago without a permit. We dropped a camera for a Level 2 inspection, documented the oversized liner and missing crown wash, then installed a properly sized DuraFlex stainless liner and rebuilt the chimney crown to stop the acidic condensate from eating the mortar joints. That job didn’t need a full rebuild. It needed the right diagnosis. That’s what Wendell brings to every chimney in North Kensington: forty years of accumulated knowledge about how these specific houses fail, and enough respect for the homeowner to show them the evidence before touching a brick.
Call Top Hat Chimney for Chimney Repair in North Kensington
If you live in North Kensington and you’re seeing mortar dust on the roof, water on the ceiling, or a furnace that sets off the carbon monoxide detector, don’t wait until the damage spreads. Call (240) 716-5865 for a free estimate. Wendell or one of his background-checked, uniformed crew members will come out, run a camera inspection, and tell you exactly what needs fixing and what can wait. That’s how we’ve worked since 1999, and that’s why homeowners across North Kensington keep our number on the fridge.
Written by Wendell Pike, Owner at Top Hat Chimney, serving North Kensington since 1999.





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