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 Leon Valley
Duct sealing in Leon Valley typically runs $450 – $1,200 for a whole-home system, with most jobs completed in a single visit after a written estimate. If you’re losing cooled air through gaps in galvanized trunk lines or watching your filter clog every few weeks, sealing is the fix that lasts.
We serve Leon Valley from our San Antonio dispatch office, and our crews know the territory: mid-century ranches near the Leon Valley Golf Course, the hillside builds off Bandera Road, and the valley-floor neighborhoods where humidity from irrigation and the Balcones Escarpment’s shifting air patterns stress ductwork differently. We’ve been driving these roads since 2004. Call us at (361) 326-5060 for a free estimate.
Why Hollis Air Duct Cleaning Is Leon Valley’s Preferred Duct Sealing Company
Our reputation in Leon Valley was built job by job, not by coupon mailers. Homeowners here talk. They mention the technician who arrived in a marked van, in uniform, and laid down a written price before touching anything. That’s The Garrison Standard, and it’s how every Hollis crew operates.
We answer our phones live, 24 hours a day, 7 days a week. No voicemail loops, no “we’ll call you back Monday.” For a Leon Valley homeowner smelling mold from a leaking return trunk on a Saturday evening, that matters.
Our technicians are background-checked and uniformed. You know who’s walking into your home before they arrive. And every repair we make carries the 365-Day Done Right Promise in writing: if the seal fails within a year, we return and make it right at no charge, including a free second visit. No negotiation, no runaround.
We know Leon Valley’s permitting process for HVAC modifications is strict enough that many hillside and valley-floor homes here have never had a permitted duct overhaul. So our sealing work often doubles as the first documented pressure test on the system. In practice, that means our crew frequently starts from a baseline of zero static-pressure data on older galvanized trunks near the Leon Valley Golf Course. We document what we find, seal what we measure, and leave you with numbers you can reference later.
Duct Insulation in Leon Valley
Duct Insulation in Leon Valley addresses a specific problem: the combination of hot attic spaces, humid air, and metal ductwork that sweats and loses thermal energy before conditioned air ever reaches your rooms. In Leon Valley’s climate, where summer attic temperatures routinely exceed 130°F, uninsulated or poorly insulated ducts can bleed 20 – 30% of your cooling capacity into the wrong spaces.
We see this most often in the 1950s – 1970s ranch homes near the Leon Valley Golf Course, where original galvanized trunks run through vented attics with nothing but thin wrap, and in the 1980s – 2000s subdivisions like Seneca and Ridgeview, where flex duct was installed with minimal insulation value. Duct Insulation in Leon Valley typically costs $800 – $2,400 depending on linear footage, accessibility, and whether we’re wrapping existing metal or replacing degraded flex with insulated product.
When Insulation Beats Sealing Alone
Some Leon Valley homes need both sealing and insulation, but others need insulation first. If your ducts are tight but your upstairs rooms never cool properly, the issue is often radiant heat gain through thin duct walls, not air leakage. We test before we recommend.
Vapor Barrier Considerations
Leon Valley’s humidity means insulation without a proper vapor barrier traps moisture against metal. We use products rated for our climate zone, with sealed seams that keep humid attic air out and conditioned air in.
HVAC Duct Sealing in Leon Valley
HVAC Duct Sealing in Leon Valley is the process of closing gaps, joints, and seams in your forced-air system so the air you pay to heat or cool actually reaches your living spaces. In a typical Leon Valley home, we measure 15 – 25% duct leakage before sealing. After proper mastic and mesh work on metal, or mechanical sealing on flex, that drops to under 5%.
HVAC Duct Sealing in Leon Valley costs $450 – $1,200 for most residential systems. The range depends on duct material (galvanized takes more labor than flex), accessibility (crawl space versus attic), and whether we’re addressing the air handler cabinet and blower compartment or just the distribution trunk lines. We price it in writing before we start, and that number doesn’t move at the door.
Pressure Testing Before and After
We run a static-pressure test on every sealed system. Leon Valley’s strict permitting history means many homes have never had this baseline documented. We give you the numbers: before leakage, after leakage, and target range for your system size.
Outbuilding and Secondary Systems
Leon Valley properties with workshop or garage HVAC systems on unpaved service drives see accelerated seal failure from dust infiltration and temperature swings. We seal these with heavier-grade mastic and metal-backed tape, not standard foil products that fail within a season.
Trusted Brands We Service in Leon Valley
Our vans carry sealing and insulation materials from Nikro, Honeywell, and Aprilaire, plus mastic and mesh systems from Abatement Technologies. We stock local parts for Leon Valley customers so we’re not ordering mid-job and leaving you waiting. For a 1969 ranch off Seneca Drive or a 2005 build in Ridgeview, we have the right product on the shelf. That means faster turnaround and fewer return trips. Our Duct Sealing team selects materials based on what your specific duct material and location demand, not what’s cheapest to buy in bulk.
Common Duct Sealing Problems We See in Leon Valley Homes
- Mastic failure on sweating galvanized trunks. In valley-floor homes near the Leon Valley Golf Course, irrigation runoff and high indoor humidity keep metal ductwork perpetually damp. Standard mastic application without proper surface prep peels within two years. We clean, prime, and apply reinforced mesh with HVAC-grade mastic rated for wet conditions.
- Ignoring the air handler cabinet and blower compartment. In 1980s – 2000s Seneca and Ridgeview subdivisions, the visible supply and return ducts look fine, but the plenum joint at the air handler and the blower door gasket leak more than the distribution system combined. We test and seal the whole air path, not just what’s easy to reach.
- Foil tape on flex duct in outbuilding systems. Temperature swings and rodent activity along unpaved service drives break standard foil tape bonds within a single season. We use mechanical clamps and UV-rated products for these applications.
- Zero documented pressure history. Leon Valley’s permitting environment means many homes have never had a proper duct assessment. Homeowners replace filters religiously but never realize they’re pulling unfiltered attic air through a leaking return. Our camera inspection finds what filter changes cannot.
Pricing for Duct Sealing in Leon Valley, TX
Whole-home duct sealing in Leon Valley runs $450 – $1,200. Duct insulation runs $800 – $2,400. Combined sealing and insulation projects typically fall between $1,200 – $3,000. These are honest ranges for our market, not teaser prices that jump once we’re inside.
What moves the number: duct material (galvanized steel takes more labor than flex duct), attic versus crawl space access, whether the air handler cabinet needs sealing too, and if we’re addressing outbuilding or secondary systems. Homes on unpaved roads or near open land often need more extensive return-side sealing due to dust loading.
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. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Leon Valley
Our crews travel throughout the region for Duct Sealing in Leon Valley and surrounding areas. We regularly work in Houston, San Antonio, Dallas, and Fort Worth. Scheduling and dispatch are coordinated from our San Antonio office, with local crews serving each metro area.
Serving Leon Valley, TX - Our Local Coverage Area
We’re based in the Leon Valley 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 Leon Valley
Every 3 – 5 years for homes on unpaved roads or near open land, versus 5 – 7 years for properties on paved streets with standard dust exposure. The unpaved-road dust loading in Leon Valley’s outlying areas pulls more particulate into return trunks, accelerating seal degradation and filter clogging. If you’re changing MERV filters every six weeks instead of every three months, your ducts likely need inspection. Call (361) 326-5060 for a free assessment.
Yes, when the mold smell comes from humid attic or crawl space air being pulled through leaking return ducts. Sealing those leaks stops the moisture source. But if mold is growing inside the duct itself, sealing alone won’t remove it. We camera-inspect first to determine whether you need cleaning, sealing, or both. The 1969 ranch off Seneca Drive we worked on had both problems: a leaking plenum pulling humid air, and dust accumulation from an unpaved access road. After sealing and cleaning, the filter stayed cleaner and the musty smell disappeared. Call (361) 326-5060 to schedule an inspection.
Temperature swings and rodent activity along unpaved service drives break standard foil tape bonds within a season. Outbuilding systems in Leon Valley also see more vibration from equipment and less frequent filter maintenance. We use mechanical clamps, UV-rated mastic, and metal-backed tape products rated for exposed applications. The material costs more upfront. It lasts. Call (361) 326-5060 for an outbuilding-specific estimate.
Sealing the return side of your system prevents it from pulling dust from attics, crawl spaces, and wall cavities. But if your wood stove or outdoor dust sources are inside the conditioned space, sealing won’t remove that particulate. You’ll need better filtration and more frequent filter changes. We evaluate whether your dust source is infiltration through leaks or indoor generation, then recommend the right fix. Call (361) 326-5060 and we’ll sort it out.
Leon Valley requires permits for HVAC modifications that alter airflow capacity or duct routing. Simple sealing of existing joints and seams typically does not require permitting if static pressure stays within original design parameters. However, because many local homes have never had documented pressure testing, we run the numbers and advise whether your project triggers permitting requirements. If it does, we handle the paperwork. The job itself doesn’t change. Call (361) 326-5060 and we’ll walk you through it.
Ready to stop losing conditioned air and start breathing cleaner? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free written estimate on duct sealing in Leon Valley. We’ll arrive in the window we quote, price it before we touch it, and stand behind the work for 365 days.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Leon Valley and the greater San Antonio area since 2004.