Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
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AfterFast, Reliable Duct Repair & Sealing Across Alamo Heights
Duct repair and sealing in Alamo Heights typically costs $280-$780 for most homes, with full-system sealing on larger retrofit duct networks running toward the higher end. We dispatch crews from our San Antonio office and carry the equipment to handle Alamo Heights’s distinctive 1920s-1950s housing stock - joist-bay return plenums, baked attic mastic, and crushed flex runs that standard scopes miss. Call (830) 402-5110 for a written estimate before any work starts.
We’ve worked Alamo Heights long enough to know the difference between a home built for ductwork and one that had it wedged in later. The Craftsman bungalows near Broadway, the Tudor Revivals off Tuxedo Boulevard, and the Mediterranean-style homes around Alamo Heights Boulevard all share the same story: central air retrofitted into cavities never meant to carry it. That history lives in your walls now, and it shows up as uneven temperatures, dust that returns after cleaning, and cedar-season misery that no air purifier can fix.
Why CleanRun Air Duct Cleaning Schertz Is Alamo Heights’s Preferred Duct Repair & Sealing Company
Our reputation in Alamo Heights was built on what we can document, not what we claim. Since 2013, we’ve served over 52,000 homes with a written price delivered before any work begins and a photo record of every duct run before and after. That standard applies to every job in Alamo Heights, from a single mastic seal repair near the Quarry to full-system sealing in the Terrell Hills adjacency.
Alamo Heights customers specifically mention our crew identification protocol - Haven Standard Clause 3: Verified Crews means background-checked, uniformed technicians identified by name before arrival. No van pulls up unannounced. No technician enters without the homeowner knowing exactly who is coming and when.
Response time to Alamo Heights is typically same-week scheduling, with dispatch coordinated from our San Antonio office. We don’t promise same-day service because duct repair is diagnostic work that deserves a scheduled window, not a rushed slot between two other jobs.
The local knowledge that matters here is structural, not scenic. We know which Alamo Heights neighborhoods have the joist-bay return plenums, which attics hit 140°F by July, and which 1940s floor plans were modified in the 1980s with flex duct that no longer reaches the added square footage. That knowledge changes what we look for, what we find, and what we quote.
Our Duct Repair & Sealing Services in Alamo Heights
Duct Sealing
Most Alamo Heights homes lose 20-30% of conditioned air through leaks before it reaches the registers. Our duct sealing service targets the connections that matter: collar joints where flex meets metal, plenum seams in the attic, and the joist-bay returns that standard testing can’t isolate. We use mastic sealant, not tape, because tape fails in Alamo Heights attics. Every sealed joint is photographed before and after, and the static pressure improvement is documented in your job record.
Flex Duct Repair
Flex duct in Alamo Heights attics doesn’t age gracefully. The insulation degrades at 140°F summer temperatures. The inner liner collapses where it was crushed during installation or by a storage box shifted years ago. We replace damaged flex with new R-8 insulated runs, sized correctly for the airflow your system was designed to move. In a 1948 home near Olmos Park Edge, we recently found two crushed runs that had been starving the master bedroom for a decade - the homeowner thought it was just an old house being drafty.
Metal Duct Repair
Some Alamo Heights homes have original galvanized metal trunk lines from early HVAC retrofits. These corrode at seams, separate at joints, and transmit noise through thin walls. We repair accessible metal duct with proper mechanical fastening and sealant, or recommend replacement where corrosion is advanced. Every recommendation comes with a photograph showing exactly what we found and why we’re suggesting the scope we are.
Duct Insulation
Unconditioned attics in Alamo Heights are brutal on duct insulation. R-4 or R-6 flex from the 1980s and 1990s is now delivering 55°F air through a 140°F attic space, sweating on the outside and bleeding cooling dollars every minute the compressor runs. We reinsulate accessible runs with R-8 product and seal the vapor barrier. The difference shows up in temperature at the register and in load on your condenser.
Mastic Sealant Application
Mastic is the only sealant we use in Alamo Heights. It’s a water-based compound that remains flexible, fills irregular gaps, and survives thermal cycling that destroys tape in two summers. We brush or trowel mastic onto every joint and seam we access, then photograph the application. This is slow work. It costs more than a tape wrap. It also lasts, which is why Haven Standard Clause 1 requires written pricing that accounts for doing it once rather than twice.
Air Leak Repair
Air leaks in Alamo Heights homes aren’t random. They cluster at the original retrofit penetration points: where the plenum enters the attic, where flex was pulled through a tight chase, where a renovation added a register without resizing the trunk. We pressure-test the system, locate leaks with smoke and thermal verification, and repair each with documented before-and-after photography. The photo record is delivered as part of your standard job documentation - not an upgrade, not an extra.
What happens when you call
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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.
BeforeAfterTrusted Brands We Service in Alamo Heights
Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation in tight joist bays, Nikro negative-pressure extractors for source removal without cross-contamination, and Honeywell media filters and zone controls where we recommend upgrades after sealing work is complete. We don’t claim these brands make us better technicians. We name them so Alamo Heights homeowners can verify specifications independently and know exactly what equipment will be in their attic before they agree to a price. Parts for common Alamo Heights systems are stocked locally, so repairs that require replacement components don’t stretch across multiple visits.
Common Duct Repair & Sealing Problems We See in Alamo Heights Homes
- Joist-bay return plenums packed with decades of debris. In 1920s-1950s Alamo Heights homes, contractors often used framed wall cavities or floor joist bays as return-air pathways instead of installing dedicated sheet metal. These structural voids become reservoirs for lint, insect debris, and rodent activity that standard register-only cleaning never touches. We access and clean these bays under negative pressure with HEPA filtration, then seal the seams with mastic.
- Mastic seals baked to failure in 140°F attics. Original sealant applied to flex-duct collars and plenum joints in Alamo Heights attics has endured twenty to forty summers of thermal cycling. It cracks, pulls away, and turns every run into an entry point for San Antonio’s December-February cedar pollen. We remove failed material and reseal with fresh mastic rated for the temperature range.
- Crushed flex runs from original sizing or later renovation. Retrofit flex duct in Alamo Heights was often routed for the original floor plan. Added bedrooms, converted garages, and finished attics leave runs that are too long, too bent, or simply disconnected at the takeoff. The blower motor works harder, the duct sweats, and the room never reaches setpoint. We replace with properly sized runs.
- Disconnected takeoffs and open plenum connections. Thermal expansion and vibration in unconditioned Alamo Heights attics loosen mechanical connections over years. A takeoff that separated from the trunk line dumps conditioned air into the attic and pulls attic air into the return. We find these with pressure testing and smoke verification, not guesswork.
Pricing for Duct Repair & Sealing in Alamo Heights, TX
Most duct sealing jobs in Alamo Heights fall between $280 and $780. Single-point repairs - a failed mastic seal at one collar, a crushed flex run to one room - typically run $280-$420. Full-system sealing on homes with joist-bay returns and multiple attic access points ranges from $550-$780. Duct insulation replacement adds $180-$340 depending on accessible linear footage. Every price is written before work begins, under Haven Standard Clause 1. No per-vent pricing. No coupon that triples once the van arrives.
What moves the price: accessibility of the attic, extent of failed original mastic, whether joist-bay returns require access through plaster walls or can be reached from the basement or crawl, and whether crushed runs require full replacement or can be re-routed. We photograph what we find, explain what drives the scope, and deliver the written price before a single panel comes off. Free estimates. Free second opinion on any competitor’s written quote.
| Service | Typical Range in Alamo Heights |
|---|---|
| Single-point mastic seal or flex repair | $280-$420 |
| Full-system duct sealing (average home) | $550-$780 |
| Duct insulation replacement (accessible runs) | $180-$340 |
| Joist-bay return cleaning and sealing | $320-$580 |
We Also Serve Cities Near Alamo Heights
Our crews work throughout the San Antonio metro area, including Alamo Heights and neighboring Schertz, Cibolo, Universal City, and Selma. Dispatch and scheduling are coordinated from our San Antonio office. If you’re outside Alamo Heights city limits but within the service radius, the same pricing structure and documentation standards apply. Call (830) 402-5110 to confirm coverage and schedule your free estimate.
Serving Alamo Heights, TX - Our Local Coverage Area
We’re based in the Alamo Heights 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 - Duct Repair & Sealing in Alamo Heights
The musty smell is likely coming from debris in a joist-bay return plenum or a disconnected takeoff that’s pulling attic air past rodent activity. Standard duct cleaning that only services the register and main trunk line never touches these structural voids. We access the bay, remove the source material under negative pressure, seal the seams with mastic, and document the before-and-after with photography. Call (830) 402-5110 for an exact scope and written price - estimates are free.
December through February, Ashe juniper pollen counts in the San Antonio area rank among the highest in the continental U.S., and every leak in your duct system becomes an entry point for allergenic particles that bypass your filter. Sealing in autumn, before peak season, reduces indoor pollen load measurably. We’ve documented this in Alamo Heights homes where sealed systems showed dramatically lower particle counts the following cedar season. The work pays for itself in reduced medication costs and filter replacements for allergy-sensitive households.
Most leaks are accessible from the attic, basement, or crawl space in Alamo Heights homes, not through the plaster. Joist-bay returns can often be accessed from below or above the cavity. Where wall access is unavoidable, we discuss the scope and show you exactly why it’s needed before any price is written. We don’t cut plaster without homeowner authorization and photographic documentation of the necessity.
Flex duct insulation can hide a collapsed inner liner for years. The outer jacket looks intact, but airflow is restricted to a fraction of design capacity. We verify with static pressure testing and borescope inspection - the camera shows what the exterior conceals. In Alamo Heights, we find this most often on runs that were pulled through tight chases during original retrofit or compressed by storage items placed in attics decades ago.
Homes with 1920s-1950s retrofit ductwork should have seals inspected every 3-5 years and fully resealed when mastic shows cracking or pull-away. The thermal cycling in Alamo Heights attics accelerates seal degradation compared to newer homes with conditioned attics. We include seal condition assessment in every cleaning visit and photograph what we find so you can see the deterioration timeline yourself. Call (830) 402-5110 to schedule an inspection with written documentation.
Schedule Your Duct Repair & Sealing in Alamo Heights
Every job starts with a written price delivered before work begins. Every duct run is photographed before and after. Every repair is backed by our 365-Day Done Right Promise - if it’s not right, we make it right, in writing, not as a favor. Our Duct Repair & Sealing team serves Alamo Heights with the equipment and training to handle the specific failures this housing stock produces. Call (830) 402-5110 for your free estimate. A live person answers, 24/7.
Written by Tomas Reyes, Owner at CleanRun Duct Repair & Cleaning, serving Alamo Heights since 2013.
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