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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After
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AfterFast, Reliable Duct Sealing Across Commerce
Duct sealing in Commerce, CA typically runs $800 – $2,400 for a whole-home system, and every Hollis job starts with a written flat price agreed before we touch anything. We’re the Commerce crew homeowners call when their registers whistle, rooms won’t heat evenly, or that blackish, oily dust keeps coming back no matter how often they change the filter. Our technicians are background-checked, uniformed, and dispatched from the Los Angeles office with routes that keep us moving through Commerce’s compact grid efficiently. Call (361) 326-5060 for a free estimate, or read on to understand why sealing matters differently here than in any residential-only suburb.
Why Hollis Air Duct Cleaning Is Commerce’s Preferred Duct Sealing Company
We’ve been serving this corridor since 2004 as part of the Garrison Partners family, and Commerce isn’t a territory we fly into blind. Our techs know the difference between a 1950s ranch off South Eastern Avenue with original galvanized trunk lines and a low-rise apartment near the Citadel Outlets with flex duct retrofitted in the 1990s. Both have different leak patterns, and both sit close enough to freight traffic that outdoor particulate is a genuine factor in how we approach the job.
Our 365-Day Done Right Promise covers every seal in writing. If a joint opens, a mastic crack develops, or static pressure readings drift back toward where they started, we return and make it right at no charge, including a free second visit. The price you approve in writing before work starts is the price on the invoice. No per-vent add-ons, no equipment charges that appear after we’re in your attic.
Phones are answered by a live person 24 hours a day, 7 days a week. You’ll know your technician’s name before they arrive, and they’ll arrive inside the quoted window, priced in writing, with the site left clean. That’s The Garrison Standard, and it’s how we operate in Commerce on every call.
Duct Sealing Services in Commerce
Duct Sealing Services in Commerce address a problem that looks different here than in cleaner-air suburbs: we’re not just stopping conditioned air from leaking into your attic, we’re closing the pathways that pull diesel particulate, warehouse dust, and freeway exhaust into your supply and return system. Commerce’s mid-century housing stock, wedged between the 5 and 710 corridors, often has original or minimally updated forced-air systems with joints that were never properly sealed when installed. Our Duct Sealing team uses mastic and fiberglass mesh on metal trunk lines, proper mechanical connections on flex duct, and closed-cell foam on plenum and air handler cabinet joints. The goal is a system that moves only the air you paid to condition, without drawing in what’s blowing past the truck yards.
Most Commerce homeowners need sealing when they notice uneven temperatures room to room, whistling registers, excessive dust accumulation, or utility bills that climb without explanation. After source removal and HEPA filtration, sealing locks the system tight so that dust doesn’t immediately re-enter.
Whole-System Pressure Testing
We don’t guess where your leaks are. Every Hollis sealing job starts with a static pressure test and visual inspection of accessible ductwork. In Commerce’s older homes, we regularly find return pans leaking at the air handler cabinet, takeoff joints that were never sealed with mastic, and plenum seams that have worked open after decades of thermal cycling. The pressure numbers tell us how much air you’re losing before it ever reaches a register.
Mastic and Mesh Sealing for Metal Duct
Foil tape fails in Commerce’s dry heat. It peels, it cracks, it reopens the gap within a season. We seal galvanized trunk lines and plenums with water-based duct mastic reinforced with fiberglass mesh, a permanent repair that flexes with temperature changes and won’t degrade under attic heat. On a mid-century single-family house off South Eastern Avenue near the warehouse cluster, our tech found original 1950s galvanized trunk lines with open joints at every takeoff and a return pan leaking at the air handler. A camera inspection after source removal and HEPA filtration showed blackish oily dust tracking along the seams facing the truck yards, so we sealed the trunk, takeoffs, and plenum with mastic and mesh rather than just taping over it. Post-seal blower door and static pressure readings dropped enough that the homeowner’s registers were finally pushing consistent air instead of whistling.
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 Commerce
Duct Insulation in Commerce solves a problem that sealing alone cannot: heat gain in attic runs and condensation on cool supply lines in our warm, dry summers. Many Commerce homes have short duct runs that pass through unconditioned attic space, and without proper insulation, the 140-degree attic air reheats your cooled supply air before it reaches the bedroom. We insulate with formaldehyde-free fiberglass wrap or closed-cell foam board, depending on access and existing duct material, after sealing is complete. Insulating before sealing is backwards; sealing first, then insulating, gives you a system that holds temperature and doesn’t sweat.
You’ll know you need insulation when supply registers blow air that feels lukewarm even when the AC is running hard, or when you find moisture staining around ceiling diffusers. In Commerce’s low-rise apartments and older single-family homes, we see uninsulated flex duct that was laid directly on attic insulation, where it compresses, loses R-value, and picks up heat from the roof deck.
Attic Run Insulation
We wrap sealed metal or flex duct with insulation rated for the temperature swing of your attic space. In Commerce, where summer attic temperatures routinely exceed 130 degrees, this matters more than in coastal cities. The wrap is secured with proper mechanical fasteners, not tape that will degrade, and we verify that insulation doesn’t block dampers or restrict airflow at takeoffs.
Condensation Control on Supply Lines
When cool air moves through uninsulated duct in a hot Commerce attic, the metal surface sweats. That moisture drips onto ceiling drywall, breeds mold in insulation, and rusts out metal duct over time. Proper insulation with a vapor barrier stops the condensation cycle before it starts.
Trusted Brands We Service in Commerce
Our equipment roster includes Rotobrush rotary brush systems for source removal, Nikro negative-air machines for containment during sealing work, and filtration products from Honeywell, Aprilaire, and Guardsman. We stock mastic, mesh, mechanical fasteners, and insulation materials sized for Commerce’s common duct configurations, so we’re not ordering parts while your attic sits open. For sealing jobs that involve air handler cabinet modifications or plenum rebuilds, we carry Abatement Technologies HEPA filtration to protect your home’s air during the work. Every tool on our van is professional-grade, not hardware-store gear, and our techs can explain what each one does and why we’re using it on your specific system.
Common Duct Sealing Problems We See in Commerce Homes
- Foil tape slapped over gaps on original galvanized trunk lines. It peels within a season in Commerce’s dry heat and the leak reopens, often worse than before because the adhesive residue prevents proper mastic adhesion until it’s cleaned off.
- Sealing only the visible trunk in the attic while the return pan, plenum, and air handler cabinet joints stay open. Industrial dust keeps getting drawn in through these high-suction points, so the homeowner sees no real reduction in dust or odor after the “sealing” is done.
- Sealing before source removal is completed. Blackish diesel-tinted dust stays trapped inside the system and keeps coating the blower motor and coils, reducing efficiency and eventually breaking down the new seal from the inside as debris accumulates.
- Skipping duct insulation on runs that pass through hot attics. The seal holds air in, but the uninsulated duct gains so much heat that the homeowner runs the AC longer, defeating the purpose and sometimes causing condensation that damages the new work.
Pricing for Duct Sealing in Commerce, CA
A typical whole-home duct sealing in Commerce runs $800 – $2,400, depending on system accessibility, total linear footage of duct, and whether we’re rebuilding plenums or sealing existing joints only. Small apartments or partial systems may fall at the lower end; full retrofits on mid-century homes with extensive galvanized trunk line and multiple plenum repairs run higher. Duct insulation adds $400 – $1,200 depending on attic access and run length.
What moves the price: how much of the system is accessible without drywall or soffit removal, whether we need to rebuild rather than seal existing components, and whether source removal is required before sealing can begin. We do not quote per-vent pricing. One flat price per system, agreed in writing before work starts, with before-and-after photos of your own ducts so you can see what was done. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Commerce
Hollis dispatches sealing crews throughout Southern California and the Bay Area from our Los Angeles office. We regularly work in Commerce and also serve Los Angeles, San Diego, San Jose, and San Francisco with the same written pricing, background-checked technicians, and 365-Day Done Right Promise. Each city gets the same operational discipline, adjusted for local housing stock and air quality conditions.
Serving Commerce, CA - Our Local Coverage Area
We’re based in the Commerce 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 Commerce
Yes, if your post-cleaning inspection showed open joints, disconnected takeoffs, or return leaks. Cleaning removes the dust that’s already inside; sealing stops new dust, especially Commerce’s diesel-tinged industrial particulate, from entering. We also offer Commerce Dryer Vent Cleaning to address lint buildup that can compound airflow issues. We see homeowners in Commerce who clean annually but never seal, and the blackish dust returns within months because the pathways are still open. Call (361) 326-5060 and we’ll test pressure to show you exactly where your system is drawing from.
Properly sealed duct with mastic and mesh should last 10 – 15 years, but original mid-century systems in Commerce often need initial sealing after decades of running unsealed. We recommend inspection every 3 – 5 years, or sooner if you notice whistling registers, uneven temperatures, or that oily dust returning. Re-sealing is only needed if original work fails or new modifications are made. Call (361) 326-5060 for a free assessment of your system’s current condition.
It’s diesel particulate and industrial exhaust from the 5 and 710 freight corridors, plus warehouse and truck yard operations that surround Commerce’s residential areas. This isn’t normal household lint; it’s heavier, oil-based particulate that sticks to duct walls and blower components differently than standard dust. Sealing alone won’t remove what’s already there, source removal and HEPA filtration come first, but sealing is what stops it from returning. Call (361) 326-5060 and we’ll show you the difference on camera.
One flat price per system, written down and agreed before any work starts. We do not charge per vent, per register, or per linear foot. The price covers everything in the scope we agree to: inspection, source removal if needed, sealing with mastic and mesh, pressure testing to verify results, and before-and-after photos of your own ducts. No add-ons at the door. Call (361) 326-5060 for your written estimate.
Yes. Commerce’s low-rise apartments and small commercial buildings often have compact duct systems with access challenges, but our equipment is sized for tight spaces. We coordinate with property managers for common-area access, work during off-hours when needed, and leave no debris. The same flat pricing and 365-Day Done Right Promise apply. Call (361) 326-5060 to discuss your building’s specific access and scheduling needs.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Commerce and surrounding communities since 2004.