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 East San Gabriel
East San Gabriel homeowners call us when their registers blow grey film after a Santa Ana wind, or when their 1950s ranch’s original sheet-metal trunk lines start leaking conditioned air into the attic. We’re Hollis Air Duct Cleaning, and our Duct Sealing crews work the San Gabriel Valley regularly, dispatching from our Los Angeles office to reach homes from the Alhambra border blocks to the 210 freeway corridor. We know the local housing stock: the postwar ranches with galvanized ductwork, the 1980s infill stucco homes, the flex-duct retrofits from past HVAC swaps that never quite sealed right. Call (361) 326-5060 for a free written estimate before any work starts.
Why Hollis Air Duct Cleaning Is East San Gabriel’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and that track record matters in a market where fly-by-night duct cleaners come and go. East San Gabriel homeowners aren’t looking for the lowest teaser price; they’re looking for a crew that shows up uniformed, prices the job in writing, and stands behind it for a full year. Our 365-Day Done Right Promise covers every sealing job in writing: if the work fails within a year, we return and make it right at no charge, including a free second visit. Our technicians are background-checked and uniformed, and phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No callback queues.
We understand the local conditions that shape duct sealing here. The spring ash-fall from the San Gabriel Mountains, the smog drift that settles into older metal ductwork, the dry particulate loading that comes with semi-arid valley living. This isn’t generic suburbia. A crew that treats East San Gabriel ducts like they’re in a humid coastal climate will miss the actual problem.
HVAC Duct Sealing in East San Gabriel
HVAC Duct Sealing in East San Gabriel means sealing the conditioned air inside your duct system so it reaches your rooms instead of leaking into attics, crawl spaces, or wall cavities. In this market, the job typically involves mastic-and-mesh sealing of original 1950s-70s galvanized sheet-metal trunk lines, joint reinforcement on aging flex-duct retrofits, and addressing the internal insulation shedding that plagues homes near the Alhambra/San Gabriel border blocks. A typical residential duct sealing job in East San Gabriel runs $850 – $2,400 depending on system size, accessibility, and whether we’re sealing a partial retrofit or a full original trunk-and-branch system. We price by the system, not by the vent, and we write the number down before any work starts.
Sealing Original Metal Trunk Lines
The postwar ranches in East San Gabriel’s older tracts still run galvanized sheet-metal trunk lines with internal insulation that sheds fiber. Sealing these requires more than tape at the joints. We inspect the liner condition first, pull loose material with negative-air HEPA filtration, then apply mastic and reinforcement mesh to seal both the joints and the liner transitions. Skip the liner check, and you’ve sealed the duct but not the source of what’s blowing into the room.
Flex-Duct Retrofit Sealing
Many East San Gabriel homes got flex-duct retrofits during past HVAC swaps, and those runs often fail at the plenum connection or get crushed in tight attic spaces. We check the flex run itself before sealing gaps, because sealing a torn or compressed flex duct is wasted effort. When the flex is sound, we seal with proper collars and mastic, not zip ties and hope.
Duct Repair in East San Gabriel
Duct Repair in East San Gabriel addresses the physical damage that sealing alone won’t fix: disconnected trunk sections, crushed flex runs, corroded galvanized metal, and return-air plenums loaded with Santa Ana ash and wildfire soot. Repair costs here typically run $400 – $1,800 for localized fixes like plenum rebuilds or flex-run replacement, and $1,500 – $3,500 for more extensive trunk-line reconstruction in older homes with failing internal insulation. We always inspect with a camera first, show you what we found, and write the repair price before we cut or seal anything.
Return-Air Plenum Rebuilds
After a Santa Ana wind event or nearby Angeles National Forest fire, we routinely find return-air plenums in East San Gabriel homes packed with black soot and ash. A standard cleaning won’t suffice if the plenum walls are corroded or the internal liner is delaminating. We rebuild with solid metal and external insulation, eliminating the shedding surface entirely.
Crushed Flex Run Replacement
1980s-90s two-story infill homes in East San Gabriel often have flex ducts routed through tight attic spaces where rooflines and added insulation compress the runs. Crushed flex kills airflow and overworks the blower. We replace with properly sized, fully extended runs and secure them to maintain shape.
Trusted Brands We Service in East San Gabriel
We stock parts and sealing materials from Abatement Technologies, Guardsman, and Aprilaire for East San Gabriel jobs, and we run Rotobrush rotary brush systems and Nikro negative-air machines when cleaning precedes sealing. This means no waiting on a parts order from out of state when your 1950s ranch needs a plenum rebuild before the next Santa Ana event. We carry the filtration products and mastic compounds that match what was originally spec’d for Valley installations, and our technicians know which brands’ collar systems work with the duct gauges common in local postwar construction. Fast turnaround matters when ash season is coming and your return plenum is already compromised.
Common Duct Sealing Problems We See in East San Gabriel Homes
- Sealing over shedding internal insulation. A mastic-and-mesh seal applied over a failing liner traps fiber that keeps blowing into supply registers after the next Santa Ana wind. We inspect and address the liner first, or the seal hides the source while the problem continues.
- Chasing gaps in crushed flex-duct retrofits. Aging flex runs from past HVAC swaps often tear or compress at the plenum connection. Sealing every gap in a crushed flex run wastes money; the duct itself needs replacement first.
- Treating wildfire soot like ordinary household dust. Black particulate from Angeles National Forest fires loads differently than pet dander or pollen. We pull soot from return-air plenums with HEPA negative-air systems before sealing, or the sealed system just recirculates ash.
- Ignoring the 1950s metal trunk’s actual condition. Original galvanized sheet-metal trunk lines in East San Gabriel’s ranch tracts often have loose internal insulation and corroded joint seams. Surface tape doesn’t address either problem. We open, inspect, and rebuild as needed.
Pricing for Duct Sealing in East San Gabriel, CA
Honest pricing for East San Gabriel duct sealing starts with whole-system ranges, not per-vent teasers that balloon at the door. A typical residential HVAC duct sealing job here runs $850 – $2,400. Duct repair, when needed before or instead of sealing, typically falls between $400 – $1,800 for localized work and $1,500 – $3,500 for extensive trunk reconstruction. What moves the number: system size (a 1,200-square-foot ranch versus a 2,800-square-foot two-story), attic accessibility, whether we’re sealing accessible joints or rebuilding buried trunk sections, and whether the job follows a camera inspection that found additional liner or plenum damage.
We don’t do estimates that shift once the technician is inside. The price is written down before any work starts, and it doesn’t move. Every East San Gabriel job gets a free written estimate, and every sealed system carries our 365-Day Done Right Promise in writing. Call (361) 326-5060 for your exact quote.
We Also Serve Cities Near East San Gabriel
Our Duct Sealing in East San Gabriel crews also travel to Los Angeles, San Diego, San Jose, and San Francisco for scheduled residential and commercial duct sealing and repair work. Each Hollis location operates independently under The Garrison Standard, with the same written pricing, background-checked uniformed technicians, and 365-Day Done Right Promise.
Serving East San Gabriel, CA - Our Local Coverage Area
We’re based in the East San Gabriel 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 East San Gabriel
Every 2 – 3 years for most East San Gabriel homes, and every 12 – 18 months if you’re directly under the heaviest smog drift or near the 210 corridor where Santa Ana winds deposit the most ash. The semi-arid climate and wildfire-season particulate loading here mean ducts accumulate fine black soot rather than humidity-driven mold, so the interval is shorter than in coastal climates but longer than in dusty agricultural zones. Call (361) 326-5060 and we’ll assess your specific exposure.
Because the original galvanized sheet-metal trunk lines with internal insulation are likely leaking conditioned air into your attic and pulling unfiltered attic air back into your system. Cleaning the ducts without sealing the leaks is like bailing a boat with holes in the hull. In East San Gabriel’s 1950s-70s ranch tracts, we regularly find that sealing the trunk joints and liner transitions cuts energy waste and stops the grey film on registers more effectively than repeated cleanings alone. Call (361) 326-5060 for a camera inspection to see if your trunk lines are the real problem.
Yes, if the flex runs themselves are intact, properly sized, and not crushed or torn at the plenum. We inspect every flex run with a camera before sealing, because sealing gaps in damaged flex duct wastes your money. In East San Gabriel, many 1980s-90s retrofits were done quickly and the flex was never fully secured; we fix the support and routing issues, then seal the connections properly with collars and mastic. Call (361) 326-5060 and we’ll tell you whether your retrofits are worth sealing or need replacement.
A written estimate first, then a camera inspection of your trunk lines and flex runs, followed by HEPA-filtered negative-air cleaning if we find soot or ash loading in the return plenum. We seal accessible joints with mastic and reinforcement mesh, rebuild damaged plenums with solid metal, replace crushed flex runs, and test static pressure before and after to verify the seal. The whole process typically takes 4 – 8 hours for a residential system in East San Gabriel. Call (361) 326-5060 to schedule.
Yes. After a nearby Angeles National Forest fire or heavy Santa Ana wind event, we always pull soot and ash from the return-air plenum with HEPA negative-air filtration before sealing any joints. Sealing a system loaded with black particulate traps that soot inside, and your blower will recirculate it for months. We also inspect internal insulation more carefully during wildfire season, since heat and particulate accelerate liner breakdown in East San Gabriel’s older metal trunk lines. Call (361) 326-5060 if you’ve noticed grey or black film on your registers after recent wind events.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving East San Gabriel and the San Gabriel Valley since 2004.