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.
Fast, Reliable Duct Sealing Across Compton
Duct sealing in Compton typically runs $450 – $1,200 for a whole-home seal on original sheet-metal systems, and most jobs are scheduled within a few business days. We dispatch crews from our Los Angeles office to Compton daily, so you’re not waiting weeks for an appointment while your HVAC keeps bleeding conditioned air into the crawl space. Call (361) 326-5060 for a free written estimate.
We’ve worked on enough homes from the 1920s through the 1960s in Compton to know the pattern: original galvanized ductwork with loose joints, rust working from the inside out, and flex duct additions from the 1980s that are now cracked and pulling in unfiltered garage air. The marine layer doesn’t help. That moist onshore breeze pushes through every gap, and before long your registers smell like a wet garage even when the filters are new. Our Duct Sealing crew treats this as a repair job, not a spray-and-pray service. We find the leaks, seal them with mastic, and stand behind the work for a full year.
Why Hollis Air Duct Cleaning Is Compton’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and our Compton customers know what to expect: a uniformed technician who arrives inside the quoted window, a written price before any tool touches your ductwork, and a 365-Day Done Right Promise that covers every seal in writing. If a joint fails or a seal breaks within that year, we come back and make it right at no charge, including the second visit.
Our phones are answered by a live person 24 hours a day, 7 days a week. No callback queues, no voicemail loops. When you schedule Duct Sealing in Compton, you’re talking to a real dispatcher who knows our crew routes and can give you a real arrival window, not a four-hour guess.
Every Hollis technician is background-checked and uniformed. You know who’s walking into your home before they arrive. That’s The Garrison Standard, and it’s how we operate in Compton, Gardena, Carson, and every city we serve.
Duct Insulation in Compton
Duct Insulation in Compton addresses a specific problem: original sheet-metal trunk lines running through unconditioned crawl spaces or attics where the marine layer’s cool, moist air meets hot supply ducts in summer and cold return ducts in winter. Without proper insulation, those metal surfaces sweat. The condensation drips onto subflooring, breeds microbial growth, and rots joists. We see this constantly in the raised-foundation homes near Compton Boulevard and in the older neighborhoods between Alondra Boulevard and Rosecrans Avenue.
Our crews wrap supply and return trunks with formaldehyde-free fiberglass insulation, sealed with a vapor barrier jacket. For Compton’s climate, we typically specify R-6 to R-8 on flex duct and R-8 on rigid metal. The job runs $600 – $1,400 depending on linear feet and accessibility.
When Insulation Beats Sealing Alone
Insulation is the right call when your ducts are structurally sound but sweating through the walls. If the metal itself is rust-pitted or the joints are loose, sealing comes first. We assess both on every Compton job and quote what you actually need, not what pads the invoice.
Vapor Barrier Integrity
The outer jacket is what matters in Compton’s humid marine air. A torn or poorly taped vapor barrier pulls moisture straight to the fiberglass, where it saturates and collapses the R-value. We use pressure-sensitive tape and mechanical fasteners, not duct tape that degrades in six months.
HVAC Duct Sealing in Compton
HVAC Duct Sealing in Compton starts with understanding that your system is likely a patchwork: original galvanized trunks from the 1950s, flex duct additions from a 1980s room conversion, maybe a garage air handler retrofit with a homemade plenum. Each junction is a pressure leak. Each leak pulls unfiltered air from your crawl space, attic, or garage and dumps it into your living space. In Compton, that unfiltered air carries fine dust from the basin, pollen from the coastal sage, and enough moisture to make your ducts smell musty within weeks of any surface cleaning.
We seal with water-based duct mastic, not tape. Mastic remains flexible, fills irregular gaps, and lasts 20-plus years when applied to clean metal. A typical whole-home seal runs $450 – $1,200 in Compton, depending on system size and accessibility. We price it in writing before we start.
Plenum and Air Handler Cabinet
The biggest leak in most Compton systems is the plenum, the box where your air handler meets the ductwork. It’s often unsealed sheet metal with a dozen screw holes pulling return air from the garage or attic. We mastic every seam, every screw penetration, and every transition. Skip this, and you’ve sealed the fingers but left the wrist open.
Return-Side Leaks
Return ducts run under negative pressure, so they don’t blow air out, they suck unfiltered air in. In Compton’s older homes, return trunks often run through wall cavities that communicate with the crawl space. We test with a pressure pan and smoke pencil, then seal the actual leaks, not just the obvious ones.
Trusted Brands We Service in Compton
We stock parts and materials from Honeywell, Aprilaire, and Abatement Technologies for our Compton customers, which means faster turnaround and no waiting on freight from out of state. Honeywell media filters and Aprilaire whole-house dehumidification components integrate directly with sealed duct systems to maintain the pressure balance we create. Abatement Technologies HEPA-negative air machines are what we use during the cleaning phase that often precedes sealing on Compton’s older systems. You won’t find us improvising with hardware-store tape or consumer-grade sealants. The equipment matters because the work lasts.
Common Duct Sealing Problems We See in Compton Homes
- Original galvanized trunks with internal rust. The metal looks sound from the outside, but rust flakes have destroyed the mastic bond surface. We clean and prep before sealing, or we recommend replacement when the metal is too far gone. Sealing over rust is a temporary fix that fails within a season.
- DIY flex duct extensions with unsupported sags. Compton’s strong post-war DIY culture means many systems have flex duct strung across attics with wire hangers that have pulled loose. The sag collects debris and creates a dead zone where moisture pools. We replace damaged flex and support it properly before sealing the connections.
- Plenums built from duct board with crumbling edges. The air handler cabinet and plenum are often the leakiest part of the system, and in Compton, the original duct board has degraded from decades of vibration and marine-layer humidity. We rebuild with galvanized sheet metal and seal with mastic.
- Registers pulling air from wall cavities. In homes near Compton Creek and in the older neighborhoods south of Alondra, we’ve found return registers cut into walls that open directly to unsealed stud bays. The system pulls crawl-space air through the wall. We seal the register boot to drywall and block the cavity communication.
Pricing for Duct Sealing in Compton, CA
A typical whole-home duct sealing in Compton runs $450 – $1,200. Duct insulation adds $600 – $1,400. What moves you within that range: linear feet of duct, accessibility (crawl space vs. attic vs. finished basement), whether we need to replace damaged flex or rebuild a crumbling plenum, and whether the job includes source removal of debris before sealing.
We do not quote per-vent. We quote per system, in writing, before any work starts. The price does not move at the door. Every Compton job includes a 365-Day Done Right Promise: if a seal fails or a joint opens within a year, we return and make it right at no charge, including the second visit. Call (361) 326-5060 for a free written estimate.
We Also Serve Cities Near Compton
Our crews work daily in Gardena, Carson, Lynwood, and Paramount. Each city has its own housing stock and its own duct problems, but the approach is the same: written price, sealed mastic, year-long guarantee. If you’re near the Compton border in any of these cities, we can typically schedule you on the same route.
Serving Compton, CA - Our Local Coverage Area
We’re based in the Compton 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 Compton
The musty odor comes from marine-layer moisture entering through unsealed joints and return-side leaks, not from surface dust. Cleaning removes the debris, but if moist outside air keeps entering, the smell returns within weeks. Sealing the plenum, trunk joints, and return leaks stops the moisture source. Call (361) 326-5060 and we’ll pressure-test your system to find the entry points.
No. Fogging masks odor temporarily but does not remove the moisture source that allows microbial growth. In Compton’s marine-influenced climate, the moisture enters through leaks, not through the registers. We don’t sell fogging upsells. We seal the leaks, remove the debris source with negative-air methods, and let the dry, sealed system do the rest.
Flex duct in Compton’s older homes is often 20-plus years old, unsupported, and chewed by rodents. Signs of trouble: rooms that never heat or cool evenly, visible sags or kinks in attic flex, or debris blowing from registers after the main trunks were cleaned. We camera-inspect flex runs and quote replacement only when necessary, sealed with proper mastic connections to the rigid trunk.
The plenum, every trunk joint, every branch takeoff, the air handler cabinet seams, and all register boots. In Compton’s pre-1970 housing stock, we also inspect for rust-pitted metal that won’t hold a seal, and we prep or replace as needed. Skipping the plenum or the return-side leaks leaves the biggest pressure losses unaddressed.
Yes, significantly. Sealed return ducts pull only filtered air from your living space, not unfiltered air from the crawl space or attic. In Compton, where the onshore breeze carries basin dust and coastal sage pollen, a sealed system means your filter does the work it’s designed to do instead of being bypassed by leaks. Most homeowners notice less dust on surfaces within two weeks of sealing.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Compton since 2004.




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