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 Sealing Across Helotes
We dispatch to Helotes from our San Antonio office, and most days we’re pulling into driveways off Bandera Road or Scenic Loop Road within the scheduling window we gave you. If you’re in Helotes and your upstairs never matches the thermostat, your energy bills keep climbing, or you’re tired of dust blowing from registers even after cleaning, there’s a good chance your ductwork is leaking in the attic. Call us at (361) 326-5060 and we’ll send a uniformed tech who’ll price the job in writing before touching anything.
Why Hollis Air Duct Cleaning Is Helotes’s Preferred Duct Sealing Company
We’ve been sealing ducts in Helotes long enough to know the local housing stock inside and out. The mix of 1970s ranch homes and newer custom builds on acre-plus lots means no two attics are the same, and crews who treat every job like a standard suburban tract house miss the mark here.
Our technicians are background-checked, uniformed, and expected to perform under The Garrison Code: arrive inside the window, price in writing, complete the job by the book, leave the site clean. Every duct sealing job in Helotes carries our 365-Day Done Right Promise in writing. If the seal fails or the leak returns within a year, we come back and make it right at no charge, including a free second visit.
Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to get on the schedule.
Duct Sealing Services in Helotes
Duct Sealing Services in Helotes address the leaks, gaps, and disconnected runs in your attic ductwork that waste conditioned air and pull in dust, pollen, and attic heat. A typical duct sealing job for a single system in Helotes runs $400 – $850, with multi-system homes ranging $1,200 – $2,400 depending on access and the extent of leakage. We use mastic sealant and mechanical fasteners on plenum joints, collar connections, and flex duct transitions, then pressure-test to verify results.
Leak Detection and Mapping
We pressurize your duct system and use smoke pencils and thermal imaging to find every leak, not just the obvious ones near the air handler. In Helotes, where long attic runs on custom homes hide disconnected flex ducts under blown insulation, this step separates a real fix from a band-aid.
Plenum and Collar Sealing
The plenum, where your air handler connects to the main trunk, is the highest-pressure joint in the system. We seal these with duct mastic rated for high-static applications, not foil tape alone, which dries out in Helotes attics within a couple of seasons and peels away.
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.
Duct Insulation in Helotes
Duct Insulation in Helotes protects sealed ductwork from the extreme attic temperatures that hit from May through October. Even perfectly sealed ducts will bleed heat if the insulation is crushed, wet, or missing on long attic runs. A typical duct insulation job in Helotes runs $600 – $1,400 per system, depending on linear footage and whether we’re re-wrapping existing trunks or replacing water-damaged flex. We use Guardsman duct wrap and Nikro negative-air containment to keep fibers out of your living space during the work.
Attic Trunk Re-Wrapping
On long ranch-style or custom-home attic runs, insulation gets compressed by workers, pests, or its own weight over time. We remove the damaged wrap, seal any newly exposed leaks, and reinstall to R-6 or R-8 standard so your conditioned air arrives at the register at the temperature your system intended.
Condensation and Moisture Control
Helotes humidity means cold supply ducts in hot attics can sweat, soaking fiberglass insulation and breeding mold. We check for proper vapor barrier orientation and add insulation where gaps create temperature differentials that lead to moisture problems.
Trusted Brands We Service in Helotes
We carry professional-grade equipment from Rotobrush, Nikro, and Guardsman, the same tools commercial crews use on larger jobs. For Helotes homeowners, that means we stock the right duct wrap, mastic, and collar fittings to complete most jobs without waiting on parts. Our rotary brush systems and negative-air machines are built for the long attic runs and multiple systems common in Helotes custom builds. We also source filtration products from Honeywell and Aprilaire when your duct sealing project includes upgrading return air pathways.
Common Duct Sealing Problems We See in Helotes Homes
- Disconnected flex runs buried in attic insulation. On large-lot Helotes homes, flex duct runs can stretch 40 feet or more from trunk to register. We’ve found completely separated runs blowing conditioned air into blown insulation while the bedroom register wheezes. The homeowner only knows something’s wrong because one room never cools.
- Foil tape failure on high-static plenum joints. Helotes attics regularly exceed 130°F in summer. Foil tape adhesive breaks down fast under that heat and the vibration of a running air handler. We see tape hanging in ribbons while the joint underneath leaks hundreds of CFM into the attic.
- Multi-system homes quoted as single-system jobs. A Helotes custom home with three air handlers needs three separate leak maps, three pressure tests, and three documented seal jobs. One blanket quote almost always means the outlying system never gets proper attention.
- Crushed or kinked flex on long attic trunks. The long runs that serve Helotes’s larger homes sag between supports, creating restrictions that raise static pressure and force leaks at weaker joints. Sealing without addressing the kink just moves the problem downstream.
Pricing for Duct Sealing in Helotes, TX
A single-system duct sealing in Helotes typically runs $400 – $850. Multi-system homes, which are common here, range $1,200 – $2,400. Duct insulation adds $600 – $1,400 per system depending on linear footage and material condition. What moves the price: how many systems you have, how accessible your attic is, whether we’re repairing disconnected runs or just sealing intact joints, and whether insulation replacement is needed. We give you one flat price per system, agreed in writing before any work starts. No per-vent pricing, no add-ons at the door. Call (361) 326-5060 for a free estimate.
We Also Serve Cities Near Helotes
Our crews work throughout the northern San Antonio metro area. We regularly seal ducts in Helotes, San Antonio, Bulverde, Converse, and Universal City. Scheduling and dispatch are coordinated from our San Antonio office, with local crews serving each area.
Serving Helotes, TX - Our Local Coverage Area
We’re based in the Helotes 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 About Duct Sealing in Helotes
No. We price per system because each air handler has its own supply and return network that needs separate leak detection, sealing, and pressure verification. A single-system quote on a three-system Helotes home guarantees the outlying attic runs get skipped. Call (361) 326-5060 and we’ll map each system and price them individually before any work starts.
Cedar fever season (December through February) drives more duct cleaning calls than sealing calls, but the same pollen infiltration points, loose collar connections and gaps at attic penetrations, are what let cedar pollen recirculate through your HVAC. Sealing those entry points during cooler months means less pollen load inside when the next season hits. Call (361) 326-5060 to schedule before December.
You’ll receive a written leak summary for each system, before-and-after pressure test readings, and photos of the sealed joints and any repaired runs. We document the work because you can’t inspect it yourself, and we stand behind it with our 365-Day Done Right Promise in writing. Call (361) 326-5060 to book.
Yes. New construction in Helotes, especially custom builds on large lots, often uses flex duct installed before final trades kick and crush runs. We’ve tested two-year-old homes with 25% leakage at rough-in joints the builder never sealed. The homeowner assumed new meant tight. Call (361) 326-5060 for a leakage test.
Sealing stops air from escaping; insulation stops heat from moving through the duct wall. In Helotes, where attic temperatures exceed 130°F for months, sealed ducts with failed insulation still bleed cooling capacity. We seal first, verify with pressure test, then address insulation gaps so your conditioned air arrives at the register at the right temperature. Call (361) 326-5060 for a combined estimate.
At a custom home off Scenic Loop Road with three air handlers, our tech found a disconnected flex run and crushed insulation on the longest attic trunk, so the system was pulling hot attic air and blowing it into a back bedroom. We sealed the leaks at the plenum and collars, re-insulated the trunk with Guardsman duct wrap, and rebalanced registers so all three systems stopped short-cycling. The homeowner said the upstairs finally matched the thermostat for the first time since they moved in.
Because so many Helotes homes are custom builds on large lots with two or three separate HVAC systems serving long attic duct runs, duct sealing here is rarely a one-system job. Each air handler has its own network of supply and return ducts, so leaks have to be found and sealed per system, not once for the whole house. That multi-system reality is far less common in older, tighter San Antonio neighborhoods inside Loop 1604. Our Duct Sealing team prices every system individually, tests every system separately, and documents every system in writing. If you’re in Helotes and you’ve been quoted a single flat rate for a multi-system house, you’re likely paying for one system and getting none of them done right.
Ready to stop throwing conditioned air into your attic? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free estimate. We’ll arrive inside the window, price the work in writing before we start, and back every seal with our 365-Day Done Right Promise. That’s The Garrison Standard, and it’s how we work in Helotes.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Helotes since 2004.