Fast, Reliable Duct Repair & Sealing Across Cypress
Duct repair and sealing in Cypress, TX typically costs between $180 for minor mastic touch-ups and $1,200 for full flex duct replacement in flood-affected runs, with most jobs completed same-day. We’re Lone Star Air Duct Cleaning Service Houston, and our Duct Repair & Sealing team works the Cypress market weekly — from Bridgeland to Fairfield Village to the older sections of 77429. Scott Gray, our owner and lead technician, brings 20 years of hands-on ductwork experience to every Cypress job. Call (855) 683-5929 for a free estimate and we’ll get you on the schedule, usually within 24–48 hours.
Why Lone Star Air Duct Cleaning Service Houston Is Cypress’s Preferred Duct Repair & Sealing Company
We’ve built our reputation in Cypress one job at a time. Our 433 verified reviews average 4.9 stars, and a growing share of those come from homeowners in 77429 and 77433 who found us after franchise crews couldn’t diagnose their recurring mold or airflow issues. Owner-led, every job — Scott Gray personally handles the inspection, the repair plan, and the sealing work. That matters in Cypress, where post-Harvey duct contamination and attic heat collapse require someone who’s seen both problems hundreds of times, not a rotating technician following a checklist.
Our response time to Cypress is typically same-day or next-day. We know the area: the master-planned subdivisions with their slab-on-grade construction and attic-flex systems, the flood-prone zones along Cypress Creek, the difference between a 1995 Perry Homes build and a 2012 Meritage install. Two decades of hands-on experience means we spot the patterns — black staining at slab-level returns, collapsed inner liners in 130°F attics, failed mastic at plenums — that less experienced crews walk right past.
Our Duct Repair & Sealing Services in Cypress
Flex Duct Repair
Cypress’s housing stock is dominated by 1990s–2010s production builds with flexible ductwork routed through attics that routinely exceed 130°F. That heat degrades the jacket, collapses the inner liner at connections, and turns your duct run into a kinked garden hose. In the Bridgestone Lakes section of 77433, we repaired a flex duct run where the inner liner had collapsed from attic heat and flood-wicking had stained the boot. We used mastic sealant and new insulation to restore airtightness and prevent condensation that could spawn mold within weeks. We cut out the damaged section, splice in new flex with proper supports, and seal every connection so it holds against Cypress’s punishing attic environment.
Duct Sealing
Any duct leak on the supply side draws unconditioned attic air into your system. In Harris County’s subtropical humidity — averaging above 70% RH for much of the year — that creates instant condensation points. We’ve sealed ducts in Towne Lake homes where the homeowner’s “allergy season” turned out to be mold spores colonizing a leaky return. Our sealing process targets every joint, boot, and plenum connection with mastic or foil-backed tape rated for high-humidity zones. We pressure-test before and after so you see the difference in CFM loss.
Metal Duct Repair
Older Cypress homes and some commercial spaces still have galvanized metal ductwork. The seams separate, the hangers corrode, and the insulation jacket disintegrates. We repair metal runs with proper mechanical fastening and re-insulate with wrap rated for Cypress attic temperatures. Metal ducts don’t flex — they leak at seams. We fix that.
Duct Insulation
Insulation in Cypress attics takes a beating. Floodwater wicks up from slab-level registers. Attic heat cooks the vapor barrier. We replace damaged insulation with fresh wrap, properly sealed at every penetration, so your conditioned air arrives at the register at the temperature your HVAC intended. No more 55°F air warming to 68°F in a hot attic before it reaches your bedroom.
Mastic Sealant Application
Mastic is the workhorse of duct sealing, but in Cypress’s humidity it degrades within 15–20 years. Production builders in Bridgeland, Fairfield, and Stone Gate used the minimum. We apply fresh mastic at plenums, transitions, and custom connections — brushed on thick, cured properly, built to last through the next decade of continuous cooling seasons.
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.
Trusted Brands We Service in Cypress
We stock parts and materials for fast turnaround on Cypress jobs: Rotobrush rotary systems for pre-repair cleaning, Nikro HEPA vacuums for contamination removal, and Honeywell and Aprilaire components for integration with whole-home air quality systems. When we seal a duct in a Cypress home, we’re not waiting on a parts run to Jersey Village — we’ve got what we need on the truck. Professional-grade equipment, owner-operated accountability.
Common Duct Repair & Sealing Problems We See in Cypress Homes
- Flex duct inner liners collapse from 130°F attic heat, creating airflow blockages that force the system to run continuously and develop leaks. We see this in Fairfield Village and Stone Gate especially — the attic access is tight, the ducts are long, and the heat builds until the liner folds like a straw.
- Slab-level return registers wick floodwater into ductwork during storms, leaving black staining in boots that homeowners miss until professional cleaning reveals latent mold. This is the hidden legacy of Harvey in 77429 and 77433 — water entered through returns, not visible wall damage, and sat undisturbed for years.
- Mastic sealant at plenums degrades within 15–20 years in Cypress’s humidity, causing unconditioned attic air to be drawn into supply ducts and create condensation points for mold. Every cooling season, the cycle repeats: leak, condensation, mold, repeat.
- Post-flood “cosmetic” repairs missed the ductwork entirely. Homeowners replaced drywall and flooring after 2017 but never pulled the registers. The flex duct boots stayed wet, the insulation stayed compromised, and the mold stayed put. We’re still finding these in 2024 and 2025.
Pricing for Duct Repair & Sealing in Cypress, TX
Here’s what duct repair and sealing costs in the Cypress market:
| Service | Typical Range in Cypress |
|---|---|
| Minor mastic sealant touch-up (single plenum or joint) | $180 – $280 |
| Flex duct section repair/replacement (10–15 ft run) | $340 – $580 |
| Full flex duct run replacement with new insulation | $720 – $1,200 |
| Comprehensive duct sealing (whole-system, pressure-tested) | $850 – $1,450 |
| Post-flood boot replacement with mold remediation prep | $420 – $780 |
What moves you within these ranges: attic accessibility (tight trusses take longer), extent of flood damage, whether we need to coordinate with your HVAC contractor, and how many runs are affected. We don’t quote blind — every estimate starts with a hands-on inspection by Scott Gray. Estimates are free. Call (855) 683-5929.
We Also Serve Cities Near Cypress
Our service radius covers Jersey Village, Tomball, Katy, and Cinco Ranch — but Cypress is where we do our deepest volume of duct repair and sealing work. The flood history, the housing stock, the attic heat patterns: we’ve learned this market block by block. If you’re in a neighboring city and dealing with similar issues, we’ll come. If you’re in Cypress, we probably worked your subdivision last month.
Serving Cypress, TX — Our Local Coverage Area
We’re based in the Cypress 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 Cypress
Cypress’s post-2017 housing stock in 77429 and 77433 often has hidden flood damage in flex duct boots and registers, requiring aggressive sealing and insulation to prevent mold colonization that is not as prevalent in neighboring Katy or Spring. Hurricane Harvey inundated thousands of homes along the Cypress Creek floodplain, and many owners never pulled their slab-level returns during remediation. We still find black staining and latent mold in boots that survived cosmetic repairs. If your home flooded and you didn’t have the ductwork inspected, call (855) 683-5929 — we’ll check it for free.
Attic temperatures exceeding 130°F degrade the flex duct jacket and collapse the inner liner, especially in 1990s–2010s production builds with long attic runs. The heat softens the wire helix, the liner folds, and airflow drops by 30–50% before you notice anything at the register. We repair with properly supported new flex and seal connections with mastic rated for high-heat, high-humidity environments. Call (855) 683-5929 for an inspection — estimates are free.
Every 5–7 years in Cypress’s climate, or immediately after any flooding event. The combination of continuous HVAC operation, 70%+ humidity, and attic heat accelerates mastic degradation beyond what you’d see in drier climates. We pressure-test and inspect seal condition as part of our service. Call (855) 683-5929 to schedule.
We use Rotobrush systems for pre-repair cleaning, Nikro HEPA vacuums for contamination control, and Honeywell or Aprilaire components when integrating with whole-home air quality systems. Our mastic and foil tape are commercial-grade, specified for high-humidity applications. Scott Gray selects materials based on what each Cypress job actually needs, not a one-size-fits-all kit. Call (855) 683-5929 to discuss your specific system.
Yes — proper sealing and insulation replacement eliminate the moisture sources that allow mold to colonize, but only if the contaminated materials are removed first. In Bridgeland and other post-Harvey subdivisions, we routinely find mold in boots that homeowners didn’t know were wet. We coordinate the repair sequence: inspect, identify, remove contaminated flex and insulation, then seal and re-insulate with materials that won’t create new condensation points. Call (855) 683-5929 — we’ll assess whether your issue is sealable or requires more extensive remediation.
Ready to fix your ductwork? Call Lone Star Air Duct Cleaning Service Houston at (855) 683-5929 for a free, no-obligation estimate in Cypress. Scott Gray will inspect your system personally, explain what we find, and give you an upfront price before any work begins. Same-day and next-day appointments available.
Written by Scott Gray, Owner at Lone Star Air Duct Cleaning Service Houston, serving Cypress since 2004.