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 Pomona
Duct sealing in Pomona typically costs $400 – $1,200 for a whole-home system, with most single-story tract homes falling in the $550 – $850 range. We’re local to the eastern San Gabriel Valley and our crews are in Pomona neighborhoods like Lincoln Park, Wilton Heights, and the Phillips Ranch area every week. Scheduling and dispatch run through our Los Angeles office, but the van that pulls up to your door is stocked for Pomona’s specific housing stock: pre-1970 galvanized round duct, early Mylar flex, and the rodent damage we find in citrus-era attics. Call (361) 326-5060 for a free written estimate before any work starts.
Why Hollis Air Duct Cleaning Is Pomona’s Preferred Duct Sealing Company
We’ve been part of the Garrison Partners family since 2004, and our Duct Sealing crews have worked on enough Pomona homes to know what the inspection will find before we open the attic hatch. In Lincoln Park, we regularly uncover original 1950s galvanized supply runs with pinhole leaks at every elbow. Near the 10 freeway and LA County Fairplex, we see return grilles coated with fine reddish-brown silica dust after Santa Ana wind events, pulled straight from the San Gabriel Mountains through leaky duct connections.
Our technicians are background-checked, uniformed, and expected to perform by The Garrison Code: arrive inside the quoted window, price the job in writing before touching anything, complete the work by the book, and leave the site clean. Every repair is backed by our 365-Day Done Right Promise. If the seal fails or the repair doesn’t hold, 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.
HVAC Duct Sealing in Pomona
HVAC Duct Sealing in Pomona is often the missing step after a standard duct cleaning, because cleaning the inside of a leaky system just gives the dust a new path back in. The job involves pressurizing the duct network to locate leaks, then sealing joints, seams, and connections with mastic compound and reinforced tape rated for the temperature swings these attics see. In Pomona’s pre-1980 housing stock, we also re-secure loose metal and replace crushed or disconnected sections before sealing, or the mastic won’t bond and the leak returns within a season.
Most Pomona homeowners need sealing when rooms never reach temperature, the blower runs constantly, or dust reappears within weeks of cleaning. The heavy runtime here, 8 – 10 months a year, means even small leaks add hundreds to annual energy bills.
What We Seal First
We prioritize the return side and the air handler connection. Those two points pull unconditioned attic air and fine silica dust directly into the system. Sealing them first gives the biggest immediate improvement in air quality and efficiency.
Mastic vs. Tape Alone
We use duct sealing mastic, a thick compound that remains flexible, over reinforced mesh tape. Standard foil tape dries and peels in Pomona’s attic heat. Mastic fills gaps and withstands thermal cycling. We explain where we’re applying it and why, before we start.
Duct Repair in Pomona
Duct Repair in Pomona often means fixing what decades of Santa Ana dust-loading and rodent activity have damaged. Original round galvanized duct in pre-1960 homes develops pinhole leaks and loose joints at every elbow and takeoff. Early Mylar flex in citrus-era houses collapses behind knee walls or gets chewed at the collar. Post-1980 infill systems were sized for open-window cooling and become pressure-imbalanced when sealed for modern AC operation.
We don’t seal over torn liners or crushed runs. We repair or replace the damaged section first, then seal the restored system. A typical repair-and-seal job in Pomona runs $650 – $1,400 depending on how many runs need replacement and how accessible the attic is.
Disconnected Runs Behind Knee Walls
In Wilton Heights and Lincoln Park ranches, we find supply runs that have pulled completely free of the trunk line, blowing conditioned air into the wall cavity. We reconnect, support, and seal, then verify airflow at the register with a digital manometer.
Rodent-Damaged Flex Duct
When we find chewed or nested flex, we remove the damaged section, inspect for entry points, and install new insulated flex with sealed collars. Sealing over rodent damage just traps the contamination and the leak.
Trusted Brands We Service in Pomona
Our vans carry professional-grade equipment from Rotobrush and Nikro, plus filtration and sealing products from Honeywell, Aprilaire, and Abatement Technologies. For Pomona homeowners, this means we don’t need to order parts and return another day. We stock mastic, reinforced tape, flex duct, and collar fittings sized for the original galvanized and early Mylar systems common in this market. Most sealing jobs are completed in a single visit. The equipment is commercial-grade, not hardware-store gear, and we explain what we’re using and why before we start.
Common Duct Sealing Problems We See in Pomona Homes
- Pinhole leaks in original galvanized duct. Pre-1960 Pomona tract homes have round metal runs that corrode at joints and elbows. Tape and mastic won’t adhere to oxidized metal, so we clean and re-secure the joint before sealing.
- Collapsed Mylar flex behind knee walls. Citrus-era and Lincoln Park homes with early flexible duct often have runs that have been crushed by storage or foot traffic in the attic, cutting airflow to entire rooms.
- Return grilles pulling Santa Ana silica dust. After a strong wind event, homes near the 10 freeway and Fairplex show heavy reddish-brown dust loading. Leaky returns pull this directly into the system, bypassing the filter entirely.
- Post-1980 systems trapping dust in sealed boxes. Infill and apartment conversions sized for open-window cooling become under-ventilated when sealed for AC, concentrating fine San Gabriel particulate that MERV filters alone cannot clear.
Pricing for Duct Sealing in Pomona, CA
A typical whole-home duct sealing in Pomona runs $400 – $1,200. Single-story tract homes with accessible attics usually fall in the $550 – $850 range. Two-story homes, rodent-damaged flex replacement, or extensive galvanized repair push toward the higher end. We give one flat price per system, agreed in writing before work starts. No per-vent pricing. No add-ons at the door.
What affects cost: attic accessibility, how many runs need repair versus simple sealing, whether we need to replace crushed or chewed flex sections, and the condition of the original metal. We show you camera footage of what we found, explain what needs repair and what just needs sealing, and you get the written price before we proceed. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Pomona
Our crews work throughout the eastern San Gabriel Valley and western Inland Empire. We regularly handle Duct Sealing in Pomona and surrounding communities including Diamond Bar, Montclair, Chino Hills, and Claremont. Each home gets the same written price, the same 365-Day Done Right Promise, and the same uniformed, background-checked technicians.
Serving Pomona, CA - Our Local Coverage Area
We’re based in the Pomona 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 Pomona
Santa Ana winds pull fine, reddish-brown silica dust from the San Gabriel Mountains and Cajon Pass directly into return grilles through leaky duct connections. Homes near the 10 freeway and LA County Fairplex see the heaviest loading. Sealing the return side and air handler connection stops this bypass, so your filter actually catches the dust instead of the attic pulling it past. Call (361) 326-5060 for an inspection after a major wind event.
Most 1950s galvanized duct in Pomona can be sealed if the metal is structurally sound. We clean oxidation from joints, re-secure loose elbows and takeoffs, then apply mastic and reinforced tape. Full replacement is only needed when sections are crushed, heavily corroded, or inaccessible. We show you camera footage and give a written price for either option before proceeding.
Duct cleaning removes dust already inside the runs. Sealing closes the gaps that let new dust, attic insulation, and unconditioned air re-enter after the cleaning. In Pomona’s climate, with systems running 8 – 10 months a year, a cleaned but unsealed duct network re-contaminates within weeks. Sealing is what keeps the clean intact and the blower from working overtime.
We pressurize the system and use a digital manometer to measure airflow at each register, combined with camera inspection of the trunk and branch lines. In Pomona’s pre-1980 homes, we expect to find disconnected collars, crushed flex behind knee walls, and rodent damage in early Mylar runs. We show you the footage, explain what needs repair versus sealing, and quote both in writing.
Yes. These systems were often sized for open-window cooling and become pressure-imbalanced when fully sealed for AC operation. We balance airflow across registers, verify the return path is adequate, and may recommend upgraded filtration from Honeywell or Aprilaire to handle the trapped particulate. The sealing material is the same, but the system design needs review so we don’t create an under-ventilated box.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Pomona and the eastern San Gabriel Valley.