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.
Fast, Reliable Duct Repair & Sealing Across Houston
Duct repair and sealing in Houston typically costs $280-$650 for most residential jobs, with flex-duct replacement running $180-$340 per run and whole-system mastic sealing averaging $400-$800 depending on access and duct count. Our Duct Repair & Sealing team works from our Houston office, dispatching crews daily to neighborhoods from Mayfair to Somerset Green and throughout the 77002, 77005, 77007, and 77030 ZIP codes. We answer every call live at (346) 248-1474.
Houston’s housing stock demands a specific kind of expertise. The 1920s-1940s craftsman bungalows in Houston Heights were never built for central air. Ducts got threaded through plaster walls and low-pitch attic crawls decades later, often with sharp bends and no support. Post-war tract homes in areas like South Lawn came with flex-duct systems routed through attics that hit 140°F for months straight. Both scenarios create failure patterns - crushed runs, separated joints, condensation pooling - that generic duct cleaning won’t fix. We document what we find with before-and-after photos of every run, then quote a written price before touching anything.
Why CleanRun Air Duct Cleaning The Woodlands Is Houston’s Preferred Duct Repair & Sealing Company
We’ve served Houston since expanding our operations here, with crews who know the difference between a Heights bungalow retrofit and a 1980s Spring Branch tract install. That matters when you’re deciding whether a duct run needs sealing or replacement.
Our Houston customers receive the same standard we established in 2013: a written price before any work starts, a documented photo record of every duct run before and after, and the 365-Day Done Right Promise backed in writing on every job. Haven Standard Clause 1 - Written Price Before Work - means you’ll never hear “call for a quote” from us. We put the number in writing while we’re still on site, before a single panel comes off.
Tomas Reyes built this practice on verifiable evidence, not claims. Every technician is background-checked, uniformed, and identified by name before arrival under Haven Standard Clause 3: Verified Crews. The equipment roster includes Rotobrush, Nikro, and Abatement Technologies - brands you can look up yourself. And we publish our license number on every page, not buried in a footer.
Need a second opinion? Bring any competitor’s written estimate. We’ll put our number next to it, free of charge.
Our Duct Repair & Sealing Services in Houston

Duct Sealing with Mastic Sealant
Houston’s near-year-round cooling season forces AC systems to push conditioned air through duct networks for 9 to 10 months annually. Every joint, seam, and register boot is a potential leak point. We seal accessible joints with mastic sealant - a water-based compound that remains flexible after curing, unlike tape that dries and fails in attic heat. In Houston’s 140°F attics, mastic outlasts foil tape by years. A typical mastic sealing job for a 1,500-2,500 square foot Houston home runs $400-$650, depending on duct accessibility and the number of joints requiring treatment.

Flex Duct Repair
Flex-duct liner breaks down faster in Houston than almost anywhere else in Texas. The combination of attic temperatures exceeding 140°F and 75-90% relative humidity degrades the inner liner and weakens the wire helix. We see collapsed runs, torn inner cores, and separated collars weekly in homes from Mayfair to ZIP 77030. Our crew recently worked a 1930s bungalow in Houston Heights (77007) where the original plaster walls hid a crushed flex-duct run in the attic crawl. Using camera inspection, we found a disconnected joint at the air handler and a sagging run full of decades of dust and condensation. We repaired the flex duct with a new section, sealed all joints with mastic, and insulated the run to stop future condensation; the homeowner immediately noticed better airflow and less dust. Flex-duct repair in Houston typically runs $180-$340 per run, including new flex, collars, mastic, and insulation wrap.

Metal Duct Repair
Older Houston homes - particularly 1960s-1980s construction in areas like Somerset Green - sometimes feature galvanized steel trunk lines with stamped fittings. These develop seam separations, rust-through at condensate contact points, and failed dampers. We repair accessible metal duct with proper sheet-metal patches, drive cleats, and sealed joints. Where metal duct has been modified with flex-duct branches (a common retrofit), we verify the transition integrity and reseal as needed. Metal duct repair in Houston ranges from $220 for a localized patch to $580 for trunk-line section replacement with proper supports.

Duct Insulation
Houston’s humidity creates a specific problem: supply duct surfaces drop below the indoor dew point, causing condensation at flex-duct joints and inside insulation wraps. Wet insulation becomes a mold incubator. We replace compromised insulation with fresh R-6 or R-8 wrap, sealed at all seams, and add external vapor barriers where attic ventilation is inadequate. Proper insulation also reduces thermal loss in those 140°F attics, meaning your conditioned air arrives at the register closer to the temperature your thermostat requested. Duct insulation work in Houston typically runs $280-$520 depending on linear footage and access difficulty.

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.
Before
AfterTrusted Brands We Service in Houston
Our equipment roster includes Rotobrush for mechanical agitation, Nikro for negative-pressure extraction, and Abatement Technologies for HEPA-controlled containment - brands recognized in the HVAC trade and verifiable by any homeowner researching what gets used inside their system. We stock common flex-duct diameters, mastic compounds rated for high-humidity environments, and insulation wraps suitable for Houston’s attic conditions, so most repairs don’t wait on parts. For specialized components, our Houston office coordinates same-day pickup from regional suppliers serving the Gulf Coast market.
Common Duct Repair & Sealing Problems We See in Houston Homes

- Flex-duct liner breakdown in 140°F attics. Houston’s slab-on-grade construction puts virtually all ductwork in unconditioned attics. Summer temperatures degrade flex-duct inner liners and weaken wire helixes, causing sags, collapses, and separated joints that leak conditioned air into the attic.
- Condensation and mold at flex-duct joints. With relative humidity regularly at 75-90% and AC running most of the year, supply duct surfaces frequently drop below dew point. Water collects at joints and inside insulation wraps, creating the sustained moisture mold needs - a problem that accelerates at roughly twice the rate of cities with true winter off-seasons.
- Crushed and disconnected runs in retrofitted bungalows. In Houston Heights (77007) and similar neighborhoods, 1920s-1940s homes had AC retrofit through original plaster walls and low-pitch attic crawls. Ducts were forced into sharp, unsupported bends that pool condensation and debris - configurations essentially unknown in post-war suburbs like Bellaire or Meyerland.
- Hurricane Harvey legacy contamination. Thousands of homes in ZIP codes like 77002 and 77007 had ductwork contact contaminated floodwater in 2017. Even where systems were cleaned, residual corrosion at metal joints and compromised flex-duct collars continue to create failure points that standard maintenance misses.
Pricing for Duct Repair & Sealing in Houston, TX
Most Houston homeowners pay between $280 and $650 for duct repair and sealing work, with specific jobs falling as follows:
- Single flex-duct run repair/replacement: $180-$340
- Mastic sealing of accessible joints (typical residential system): $400-$650
- Duct insulation replacement: $280-$520
- Metal duct patch or section replacement: $220-$580
- Whole-system assessment with camera inspection and written scope: $0 (free estimate)
What moves a job toward the higher end: multiple attic access points, extensive crushed or disconnected runs requiring geometry correction, contaminated insulation removal, or limited crawl space that extends labor time. What doesn’t affect price: number of vents or registers - we don’t charge per-vent. Haven Standard Clause 1 means one flat price per system, agreed in writing before work starts. No exceptions since 2013.
Every estimate includes the documented photo record of every run, delivered as part of the standard job record. Call (346) 248-1474 for a free written estimate.
We Also Serve Cities Near Houston

Our Houston office dispatches crews throughout the metro area, including Galena Park, Bellaire, Humble, and Spring. The same written-price guarantee, documented photo record, and 365-Day Done Right Promise apply in every city we serve.
Serving Houston, TX - Our Local Coverage Area
We’re based in the Houston 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 Houston

The duct geometry is usually the root problem. In Houston Heights bungalows built in the 1920s-30s, AC was retrofitted through original plaster walls and low-pitch attic crawls, creating sharp, unsupported bends and sags that pool condensation and debris. Cleaning removes the buildup but doesn’t fix the geometry causing it. We correct the duct layout first, then seal and insulate - otherwise the problem returns. Call (346) 248-1474 for a free assessment with camera inspection.
Houston’s 75-90% relative humidity means supply duct surfaces frequently drop below indoor dew point, causing condensation at joints and inside insulation. Standard tape seals fail faster here than in drier Texas metros. We use mastic sealant, which remains flexible after curing and withstands attic humidity cycles better than tape alone. For humid Houston attics, mastic is the appropriate specification. We quote the sealing method in writing before starting.
Yes, particularly in flex-duct systems with compromised insulation or separated joints where condensation has been pooling. Houston’s near-year-round cooling season means biological growth accumulates at roughly twice the rate of cities with winter off-seasons. We document any mold with photos, explain the moisture source causing it, and include remediation options in the written scope. The photo record lets you see what we found rather than taking our word. Call (346) 248-1474 to schedule.
Our repair and sealing work uses professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies - trade-recognized brands customers can research independently. For sealing specifically, we apply mastic compounds rated for high-humidity environments and use mechanical fastening methods appropriate to the duct material. We name the specific equipment and materials in our written scope so you know what you’re paying for before work begins.
Because Houston is almost entirely slab-on-grade with no conditioned basements, virtually all ductwork sits in attics that routinely exceed 140°F in summer. This accelerates flex-duct liner breakdown and joint separation. It also means every repair requires attic access, often in cramped, high-temperature conditions that extend labor time compared to basement-accessible systems in other regions. We factor actual access conditions into our written price, not a flat rate that changes on arrival.
Ready to see what’s actually inside your ductwork? Call (346) 248-1474 for a free written estimate. We’ll inspect every run with a camera, show you the photos, and put a flat price in writing before any work starts. Every job is backed by our 365-Day Done Right Promise and the full H.A.V.E.N. Standard.
Written by Tomas Reyes, Owner at CleanRun Air Duct Cleaning The Woodlands, serving Houston since expanding operations from our established 2013 practice.




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