Gelco Chimney Liner & Rebuild Nationwide

Gelco Chimney Liner & Rebuild in Gaithersburg: What to Know First

Gelco chimney liner and rebuild work in Gaithersburg typically runs $2,400-$6,800 depending on whether you need a liner replacement alone or a partial-to-full masonry rebuild above the roofline. We complete most Gelco liner jobs in one day; rebuilds take two to four days depending on weather and how much brick needs to come down. As an independent Gelco service provider, we are not affiliated with or authorized by Gelco, but our techs work on their liners every month across Montgomery County, and we quote a written price before any work starts, no exceptions. If you own a Gelco liner and something looks or smells wrong, call (240) 220-9395 and we will put a camera down the flue before we recommend anything.

Call (240) 220-9395

This page is for Gaithersburg homeowners who bought a home with a Gelco liner already installed, or had one put in years ago and now need to know if it is still doing its job. Corrine Halstead and the crew at Level Two Chimney Gaithersburg have been servicing this area long enough to know which Gelco liners hold up in Maryland’s freeze-thaw cycle and which ones do not.

How Gelco Products Fail - and How We Fix Them

Gelco makes a range of stainless steel chimney liners, and most of what we see in Gaithersburg homes are their flexible and rigid liner systems installed between 2005 and 2018. Here is what actually goes wrong with them, based on what our camera shows us, not guesswork.

• Gelco flexible liner seam separation at the corrugation peaks. Gelco’s flex liners use a continuous strip of 316L or 304 stainless, but the corrugated profile creates stress points where the metal flexes most. In older installations, especially those venting a furnace or boiler with acidic condensate, the peaks of the corrugations start to corrode first. You will not see it from the firebox. The camera shows pinhole light bleed in a line along the flue. Fix: full liner replacement, sized to the appliance, not just the old liner diameter.
• Improper diameter sizing from the original install. We regularly pull out Gelco liners in Gaithersburg that were a full inch too small for the fireplace opening. A 6-inch liner on a fireplace that needs 8 inches leads to smoke rollout, slow-burning fires, and accelerated creosote accumulation in the bottom third of the liner. The fix is not a band-aid. It is a correctly sized Gelco replacement, or a comparable aftermarket grade like DuraFlex where the specs match better.
• Rigid Gelco liner sections separating at the flue tile transition. Rigid Gelco liner kits rely on stove pipe style joints that can separate when the chimney above shifts, which happens in Gaithersburg’s clay soil. Older brick-stack homes near the Rio Washingtonian Center corridor show this pattern. The liner separates just below the flue tile, exhaust leaks into the chimney cavity, and you get a creosote smell in the attic. Fix: pull the upper sections, resecure with a proper locking band, and verify with camera footage from top to bottom.
• Condensate corrosion on the interior wall of Gelco liners venting gas appliances. Gas exhaust is wet and acidic. Gelco liners are rated for gas, but the wall thickness matters. Thin-wall liners installed as a budget option in the 2010s develop interior rust bloom within a decade. The outside looks fine. The camera shows orange streaking and shallow pitting. Fix: replace with a 316L alloy liner with a higher molybdenum content, which handles condensate better than 304.
• Failed top plate and storm collar seals after freeze-thaw cycling. The Gelco liner itself may be fine, but the top plate and storm collar at the crown are the first place water gets in. Gaithersburg winters freeze and thaw repeatedly, and silicone caulk eventually lifts. Water runs down the outside of the liner and sits on the smoke shelf. Fix: new top plate, new storm collar, mechanical fastening instead of caulk-only, and a crown seal we can photo-document for you.

Our Gelco Chimney Liner & Rebuild Process

Every Gelco job in Gaithersburg follows the same sequence. No shortcuts, and you get photos at every stage.

1. 1
   Camera inspection first. We run a camera down the flue from the crown, not up from the firebox, so we see the entire liner profile in one pass. You watch the footage with us, or we send it to your phone while we are still on site.
2. 2
   Written quote with measurements. Corrine pulls measurements and photos into every estimate. You get a line-item price, a scope of work, and a written warranty. Nothing starts until you sign off. Haven Standard Clause 1: written price, written scope, written warranty.
3. 3
   Parts decision. We stock OEM Gelco components where they are still manufactured, and we use quality aftermarket equivalents from DuraFlex or HeatShield when the OEM part is discontinued or inferior for the application. You know exactly what goes into your chimney and why.
4. 4
   Liner install or rebuild. For liners, we size correctly, insulate where the manufacturer requires it, and connect with a locking top plate. For rebuilds, we take down brick to a stable course, then reline and rebuild with a proper crown and cricket where the roof geometry demands it.
5. 5
   Verification pass. After the install, we run the camera again. You get before and after footage. Clause 4 of the Haven Standard requires a photo record on every job, and we have done that on every job since 2009.
6. 6
   Cleanup and documentation. We leave the area cleaner than we found it. You leave with the written warranty, the camera record, and our phone number if anything ever looks off. 365-Day Done Right Promise: if it’s not done right, we make it right.

Before

After

What Gelco Chimney Liner & Rebuild Costs in Gaithersburg

Real numbers, not a call-for-pricing wall. Here is what we see across Gelco jobs in this area:

We do not quote over the phone without eyes on the chimney. But when we arrive, the written price is in your hand before any work starts, and that price does not creep. Estimates are free. Call (240) 220-9395 to schedule a camera inspection.

Why Gaithersburg Homeowners Call Level Two Chimney Gaithersburg for Gelco Work

Most companies in this area will look at a Gelco liner with a flashlight and tell you it needs replacing. We will show you the camera footage and let you decide. That difference matters, because a Gelco liner that looks rough at the top cap may have ten years left in the body, and a liner that looks fine from the firebox may be Swiss cheese at the corrugation peaks. Corrine has been pulling the camera out before quoting anything since her crew started working Montgomery County chimneys, and that practice is why people around Gaithersburg keep our number.

We also carry multi-brand backup. If a Gelco OEM part is backordered or discontinued, we can substitute a DuraFlex or HeatShield component and tell you exactly why it matches or exceeds the original spec. You are never stuck waiting on a part that may not exist. Every job includes our 365-Day Done Right Promise, a written price before work starts, and a documented photo record before and after. The camera doesn’t guess. Neither do we.

FAQs