Duct Repair & Sealing in Alamo Heights - We Measure the Leak Before We Quote

Fast, Reliable Duct Repair & Sealing Across Alamo Heights

Duct repair and sealing in Alamo Heights typically costs $280-$680 for most residential jobs, with flex duct rerouting through closets or soffits adding $150-$400 when original plaster ceilings can’t be disturbed. Our crews serve Alamo Heights from our San Antonio office, and we carry the camera equipment, mastic sealant, and flex inventory needed for the neighborhood’s pre-war housing stock on every truck. Call (726) 600-7155 for a written estimate before any work starts.

Call (726) 600-7155

We’ve worked the 78209 zip since 2013. That means we’ve crawled the finished attics of the 1920s Tudors near Cambridge Oval, rerouted flex runs through hall closets in the 1940s ranch homes off Broadway, and sealed shared dryer stacks in the condo buildings along Nacogdoches. Alamo Heights looks polished from the curb, but the ductwork behind those walls tells a different story - retrofitted systems, mismatched materials, and two pollen seasons that find every gap.

Why CleanRun Air Duct Cleaning San Antonio Is Alamo Heights’s Preferred Duct Repair & Sealing Company

Our reputation in Alamo Heights was built on documented evidence, not promises. Every job starts with a written price under Haven Standard Clause 1, and every duct run is photographed before and after. Homeowners here research before they call, and they stay with us because they can see what was actually done.

Reviews from Alamo Heights customers consistently mention two things: the photo record delivered at the end of the job, and technicians who knew how to work around historic finishes without damaging them. We’ve earned strong local ratings by treating plaster ceilings and original woodwork as constraints, not obstacles to rush through.

Scheduling runs from our San Antonio office means we route crews to Alamo Heights without the delays of a dispersed operation. Most appointments are available within 48-72 hours, and our trucks carry the full equipment roster - Rotobrush inspection systems, Nikro negative-pressure units, and Guardsman sealing products - so we don’t leave to fetch parts.

The local knowledge that matters here is structural. We know which blocks have pre-war galvanized trunk lines, which condo associations require pre-approved access times, and how the mature live-oak canopy along Alamo Heights Boulevard drops debris that accelerates filter bypass. That specificity saves time and prevents damage.

Our Duct Repair & Sealing Services in Alamo Heights

Duct Sealing

Most Alamo Heights homes we inspect have joints sealed with duct tape that dried out years ago. We remove that failed material and apply mastic sealant - a thick, fiber-reinforced compound that remains flexible and creates a permanent airtight bond at every connection. In pre-war homes near Cambridge Oval and the 78209 core, we often find the worst leakage at splices between original sheet metal elbows and later flex duct additions. Our sealing protocol includes negative-pressure testing after application to verify the repair, documented in your photo record.

Flex Duct Repair

Flex duct in Alamo Heights fails differently than in newer construction. Retrofitted runs in 1920s-1950s homes were often pulled through attic spaces never designed for HVAC, resulting in compression, sagging, and kinks that restrict airflow and tear the inner liner. When the original galvanized trunk line sits above an intact plaster ceiling - common in the Tudor Revival and Colonial homes between Broadway and Nacogdoches - we scope the damage with a camera and often reroute new flex through closets or soffits rather than cut access holes. On a 1938 Tudor Revival near Cambridge Oval, our tech found the original galvanized trunk line hidden above an intact plaster ceiling with a badly sealed splice feeding a 1990s flex run. We scoped the main trunk with a camera inspection and rerouted a new flex duct through a hall closet, then sealed every joint with mastic and replaced a failed Aprilaire filter cabinet connection at the air handler. Post-repair negative pressure testing showed the return-side leakage that had been pulling live-oak pollen into the supply and return ducts was closed.

Metal Duct Repair

Original galvanized steel trunk lines in Alamo Heights pre-war homes corrode from the inside out, especially where condensate collects at low points in the attic. We patch accessible sections with matching gauge metal and seal with mastic, or recommend full replacement when corrosion has compromised structural integrity. In homes with finished attics - the 1940s and 1950s ranches off Contour Drive are typical - access is slow and methodical. We photograph every stage so you see what the ceiling concealed.

Duct Insulation

Alamo Heights attic temperatures exceed 130°F in summer, and uninsulated or degraded flex duct loses capacity fast. We install foil-faced insulation with proper vapor barriers, sized to the duct diameter, and secure it with tension straps rather than tape that will fail. In homes where flex runs through closet soffits, we use insulation rated for the reduced clearance and document the installation with photos at each turn.

Mastic Sealant

Mastic is our standard at every joint, not an upgrade. We apply it with a brush at all connections - plenum to trunk, trunk to branch, branch to flex - and embed fiberglass mesh at stress points. In Alamo Heights, where mountain cedar pollen infiltrates through gaps smaller than a pencil lead, this matters. The mastic we use remains flexible from 20°F to 200°F, which covers the full range of attic conditions in 78209.

Air Leak Repair

Leak detection starts with a calibrated pressure test of the entire duct system. We seal the registers, pressurize the ducts, and measure leakage against the blower capacity. In Alamo Heights homes with multiple additions and retrofits, we often find the total leakage exceeds 30% of rated airflow - air you’re paying to condition that never reaches a room. We map the leaks, repair with appropriate materials, and retest to verify improvement.

Dryer Vent Sealing

Shared dryer vent stacks in Alamo Heights apartments and condos present a distinct problem. The vertical run serves multiple units, but only the ground-floor trap gets regular cleaning. Lint accumulates in the shared shaft, restricting airflow, extending dry times, and creating fire risk. We clean the full vertical run from roof cap to connection points, seal joints between floors with high-temperature mastic, and install proper backdraft dampers where they’re missing. We coordinate with building management for access and document the work for association records.

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Trusted Brands We Service in Alamo Heights

Our trucks carry professional-grade equipment from manufacturers whose specs you can verify yourself: Rotobrush for camera inspection and mechanical agitation, Nikro for negative-pressure extraction, and Guardsman for sealing and coating applications. We stock flex duct, mastic, and fittings sized for the range of systems found in Alamo Heights homes, from 6-inch round branch lines to 16-inch galvanized trunk sections. For filtration components, we install and repair Aprilaire and Honeywell media cabinets - the same brands specified by most HVAC manufacturers. Parts availability means most Alamo Heights repairs are completed in a single visit, with no return trip to source materials.

Common Duct Repair & Sealing Problems We See in Alamo Heights Homes

• Retrofitted attic runs with failed tape joints. Early sheet metal elbows spliced to later flex duct with duct tape and no mastic - every joint leaks, and every leak pulls in Hill Country cedar pollen during December through February. We find this in nearly every pre-1960 home we inspect in 78209.
• Sagging flex runs in finished attics. The 1920s-1950s homes near Alamo Heights Boulevard and Contour Drive have attics converted to storage or living space, with flex duct compressed against roof decking or pulled tight around framing. Airflow drops. The blower works harder. Energy bills rise without explanation.
• Shared dryer vent stacks in multi-unit buildings. The vertical lint pathway runs several floors, but only the trap-end lint gets removed. The shared shaft clogs progressively, and individual unit owners have no access to clean it. We coordinate with building management and clean the full run.
• Filter bypass from poorly sealed return plenums. Alamo Heights’ two pollen peaks - mountain cedar December-February, live oak March-April - overwhelm standard filters when the return plenum pulls unfiltered air through gaps around the filter rack. The Aprilaire and Honeywell cabinets we install seal the filter perimeter and prevent bypass.

Pricing for Duct Repair & Sealing in Alamo Heights, TX

We Also Serve Cities Near Alamo Heights

Our crews work throughout the metro area, with regular routes to Alamo Heights and neighboring communities. We also handle Duct Repair & Sealing in San Antonio, Castle Hills, Terrell Hills, and Leon Valley - each with its own housing stock and ductwork characteristics, but all served with the same written pricing and documented photo record.

FAQs - Duct Repair & Sealing in Alamo Heights