Sweep & inspection
Caps & crowns
Flue relining
Masonry repair
Gas fireplace serviceLevel 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.
Gelco Chimney Cleaning in San Antonio, TX | Alcott Chimney San Antonio
We provide independent San Antonio Chimney Sweep and Gelco repair across San Antonio, from King William’s historic masonry stacks to the prefab fireplaces in newer subdivisions off 1604. The thing that makes our Gelco work here different: we know exactly how local freeze-thaw cycles, hail, and chimney swifts damage these systems, and we price the fix plainly before we touch anything. Call (903) 515-5079 and we’ll tell you what a sweep costs and what we actually expect to find inside your flue.
We’re not a manufacturer affiliate or an authorized Gelco service center. We’re independent. That matters because we recommend what holds up in San Antonio, not what a brand rep tells us to push. Our techs work on Gelco clay tile liners, cast-in-place flues, stainless caps, and multi-flue crowns every week, and our familiarity with their common failure points runs deep. We cover all of San Antonio: Alamo Heights, Monte Vista, King William, Stone Oak, Windcrest, you name it. Get in touch at (903) 515-5079 for a written estimate before any work begins.
Why San Antonio Residents Choose Us for Gelco Service
Ruben Castellano started his trade at Los Angeles Trade-Technical College’s building and construction program, then spent years working chimneys across the Southwest before settling into San Antonio work well over a decade ago. We’ve cleaned and repaired Gelco systems in everything from 1920s bungalows in Monte Vista to sprawling post-war tract homes near Windcrest. Ruben’s known for telling customers exactly what he found inside the flue and what it costs to fix. No vague warnings, no upsell theater.
Every tech who shows up is background-checked and identity-verified under the Threshold Standard. You get the technician’s name and photo before we arrive, and they carry a photo ID badge at the door. Every job includes a written price before work starts and a written guarantee on any repair. If a repair fails inside the coverage window, the second visit is free under our 365-Day Done Right Promise. That’s the deal we’ve run since 2002 as part of the Threshold Group family.
We also work with Gelco sales & service parts and specs daily, so we’re not guessing at liner dimensions or crown materials on the job site. We know what works, what fails, and what’s worth spending money on versus what can wait.
Styles & brands we work with





Common Gelco Chimney Cleaning Problems We Solve in San Antonio
- Freeze-thaw spalling in clay tile liners. Older King William and Monte Vista chimneys with original Gelco clay tile liners take a beating during San Antonio’s winter cold snaps. Water gets into hairline cracks, freezes, expands, and the tile face flakes off. We find this constantly after January cold fronts. Sometimes a Level 2 camera inspection shows minor spalling that just needs monitoring. Other times, the liner’s gone far enough that patching would be a genuinely bad idea.
- Cracked crown coatings from hail and summer heat. A Gelco multi-flue crown sitting on a San Antonio rooftop endures direct sun for months, then gets pounded by spring thunderstorms and the occasional hailstorm. The crown coating cracks, water seeps into the masonry below, and you end up with a leaking chimney that stains ceilings. We repair crowns and apply a breathable waterproofing sealant so water vapor can still escape the brick.
- Chimney swift nests blocking Gelco flues inside Loop 410. In the older neighborhoods inside Loop 410, Gelco flues without proper caps become nesting sites for chimney swifts, a protected bird species. The nest constricts the flue, reduces draft, and traps carbon monoxide inside the house. We handle removal carefully and legally, then install a stainless cap sized for your Gelco flue so the birds don’t come back.
- Corrosion at the cap-to-flue transition. San Antonio’s humid subtropical air means dew point gets hit almost nightly for much of the year. Gelco cap-to-flue transitions collect condensation, and over time, cheap fasteners or unsealed seams corrode. We replace with stainless or galvanized hardware that handles the humidity without rusting through in five years.
- Water intrusion through spalled brick exteriors. Brick chimneys across San Antonio lose surface material as water freezes and expands inside the masonry itself. That’s not just a cosmetic problem; once the bricks spall, water moves deeper into the stack and damages the Gelco liner system from the outside. We repair spalling brick and waterproof the structure to stop the cycle.
Gelco Service in San Antonio: What Local Conditions Mean for Your Equipment
Here’s the thing most generic brand pages won’t tell you: in King William and the surrounding historic districts inside Loop 410, chimney swifts are a protected species, and if they set up inside your Gelco flue during spring or early summer, you can’t just pull the nest out and call it done. Federal law protects them, their eggs, and their active nests. What that means for a Gelco owner in older San Antonio neighborhoods: a “simple chimney cleaning” sometimes becomes a two-part job. First, we do our Chimney Inspection in San Antonio to confirm whether birds are actually present and whether the flue is still structurally sound underneath. Second, if swifts have been nesting, we wait until the birds have left on their own, clean out the remaining nesting material, then install a properly sized Gelco cap or a stainless aftermarket cap that prevents re-entry. Homeowners in Stone Oak or other newer suburban areas rarely run into this. Their prefab units and newer flues don’t have the same open masonry profiles that attract swifts. But for anyone in a 1910s or 1920s brick chimney inside the old city grid, this is a genuinely common spring and summer issue that a basic sweep won’t address.
Gelco Models & Products We Service in San Antonio
We work on the full range of Gelco chimney products you’ll find across San Antonio: clay tile liner systems, cast-in-place flue liners, stainless steel chimney caps, and multi-flue chimney crowns. When a Gelco liner or crown needs replacement, we use OEM Gelco components where they’re available because those parts were designed to work together. But we’re honest about the exceptions. For caps and dampers, we often recommend aftermarket stainless or galvanized components that hold up better against San Antonio hail and humidity than the original Gelco units. If a Gelco clay tile liner is severely spalled or has shifted, we don’t patch it and wish you luck. We advise full replacement. A compromised liner is a fire and carbon monoxide risk, and no amount of sealant fixes structural movement.
See the difference
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AfterGelco Service Pricing in San Antonio
A standard Gelco chimney sweep in San Antonio typically runs between $180 and $340, depending on flue height, access, and the amount of creosote buildup (the tar-like residue that causes chimney fires). If the chimney hasn’t been cleaned in years or shows heavy glazing, the job takes longer and costs more. A Level 2 camera inspection adds roughly $100 to $250, and we recommend one after any notable weather event or when you’re buying an older home anywhere from Boerne to Alamo Heights. Crown repairs, waterproofing, and liner replacements are quoted separately after we see the actual condition with a camera. Every estimate is free and written down before work begins. Call (903) 515-5079 and we’ll give you a real number.
Serving San Antonio, TX - Our Local Coverage Area
We’re based in the San Antonio 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 – Gelco Chimney Cleaning in San Antonio
Yes, and it’s the single most common Gelco failure we see in older San Antonio homes. Clay tile liners are good at holding up to heat, but they’re brittle, and water that seeps into the masonry freezes when overnight temps drop, expanding and cracking the tile face. Over repeated winters, tiles spall and flake, leaving gaps in the flue. That’s exactly what we found on a 1920s bungalow in Monte Vista a few winters back. A camera inspection showed multiple spalled tiles after one cold snap. We rebuilt that flue with new Gelco tile and applied a breathable waterproofing sealant to the exterior to stop water from getting back in. If your chimney is 60-plus years old and you hear faint scraping or see tile shards at the base, call (903) 515-5079 for a camera inspection before you light another fire.
We handle it legally and carefully. Chimney swifts are a protected migratory bird species, so while they’re actively nesting, we can’t remove them or disturb the nest. In San Antonio, that active window is typically spring through mid-summer. Once the birds have left on their own, we clean out the remaining nesting material, inspect the Gelco flue for damage, and install a chimney cap sized for your flue so they can’t return. If you hear chittering sounds from your chimney between March and August, especially in older neighborhoods around King William or Monte Vista, give us a call at (903) 515-5079 and we’ll tell you what you’re dealing with.
For caps, aftermarket stainless steel is often the better choice in San Antonio, and we’ll tell you that directly. Hail and humidity are rough on caps, and aftermarket stainless units typically outlast Gelco’s original cap hardware in this climate. Where we use OEM Gelco parts is on liner and crown replacement, because those components need to match the flue dimensions exactly. Caps and dampers, though, are places where a well-made aftermarket part does the job better for less money. We’ll show you the options and the price difference before any work starts.
Yes. We use a breathable waterproofing sealant that soaks into the masonry and blocks water absorption without forming a surface film or changing the color or texture of the brick. The key word is breathable. You want water out, but you also want water vapor that’s already inside the masonry to escape. A coating that seals everything in creates worse freeze-thaw damage than no coating at all. We spec the right product for the chimney’s age and condition, and we include the waterproofing step in our crown repair and spalling brick repair work.
It does. Prefab fireplaces in post-war tract homes across San Antonio, especially outside Loop 410 toward Windcrest or Stone Oak, use a factory-built metal chimney system that usually has a Gelco-branded liner or cap component. Service on those is different: the clearances, the flue geometry, and the failure modes aren’t the same as a brick masonry chimney. You’re typically dealing with rusted metal chase tops, failed insulation, or warped damper assemblies rather than spalled clay tile. The sweep process is less about chipping away creosote and more about inspecting the metal components for corrosion and blockages. We service both, but the inspection approach and repair costs differ.
Service Areas Near San Antonio
We cover all of San Antonio proper, including Alamo Heights, Monte Vista, King William, Stone Oak, and Windcrest. We also serve San Antonio service area communities throughout Bexar County. Just outside the city, we handle Gelco service in Schertz and Gelco service in Cibolo as well as Boerne. If you’re within 45 minutes of downtown San Antonio, chances are we can get to you.
Book Your Gelco Service in San Antonio Today
We’ll describe what we found and tell you what it costs to fix, and we’d rather give you a straight answer now than a vague promise you’d have to call back about later. If you’re in San Antonio and need a Gelco chimney cleaning, inspection, or repair, call (903) 515-5079 for a free estimate and a technician who arrives announced, with a name, a face, and a written price.
Written by Ruben Castellano, Owner at Alcott Chimney San Antonio, serving San Antonio homeowners since 2002.