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 Pasadena
Duct sealing in Pasadena typically runs $450 – $1,200 for a whole-home system, and most jobs are scheduled within a few days of your call. If your registers whistle, your upstairs rooms never cool, or your power bill climbed last summer without explanation, you probably have leaks in your ductwork. We’re Hollis Air Duct Cleaning, part of the Garrison Partners family, and our Duct Sealing crew serves Pasadena from our Los Angeles office. We’ve worked the post-WWII ranches off Richey Street, the 1960s tract homes near the Ship Channel, and the slab-built houses where duct runs disappear under concrete. You can reach us at (361) 326-5060 for a free estimate, and we’ll give you a written price before any work starts.
Why Hollis Air Duct Cleaning Is Pasadena’s Preferred Duct Sealing Company
Pasadena homeowners know the difference between a crew that tapes and leaves and one that preps the surface first. We’ve been in business since 2004, and our 365-Day Done Right Promise means if a sealed joint fails within a year, we come back at no charge. That includes a free second visit, not a negotiation.
Our technicians are background-checked and uniformed, and they arrive inside the quoted window. Phones are answered by a live person 24 hours a day, seven days a week. No voicemail loops, no callback queues.
We understand Pasadena’s housing stock: slab foundations with buried duct chases, attic flex lines that sweat through August, and that fine oily film from refinery emissions that coats every surface it touches. Generic duct sealing skips the prep. We don’t.
HVAC Duct Sealing in Pasadena
HVAC Duct Sealing in Pasadena starts with understanding what your ducts are actually coated with. This isn’t dust-country Arizona. The petrochemical plants along the Ship Channel and the diesel traffic on the 225 put a sticky, corrosive film into the air that settles inside ductwork. Standard mastic or foil tape slapped over that film will fail within a season; the soot is a release agent. Our process begins with solvent degreasing, then mastic application on properly prepped metal.
Most Pasadena homes built between 1945 and 1985 have either attic duct systems or slab-embedded runs. Attic flex in Gulf Coast humidity sweats, rots, and pulls loose at every joint. Slab ducts leak into the soil, and you won’t find the breach without a camera. A typical HVAC duct sealing job in Pasadena runs $450 – $950 for attic systems and $650 – $1,200 for slab or chase work requiring access and inspection.
Attic Duct Systems
Attic ducts in Pasadena’s older ranches bake all summer, then cool overnight, creating condensation that soaks foil tape and loosens mastic. We remove degraded material, degrease with Guardsman cleaner, and seal with rated mastic rated for the temperature swing. Our Nikro negative-air machines keep debris contained while we work.
Slab and Buried Runs
When ducts run under a Pasadena slab, leaks are invisible. We scope the line with a camera, mark the breach, and access it through a minimal floor cut or chase opening. Sealing here is repair, not maintenance; the cost reflects the diagnostic work and the precision required.
Duct Repair in Pasadena
Duct Repair in Pasadena often means fixing what decades of humidity and refinery soot have destroyed. Original galvanized trunk lines in post-WWII homes corrode from the inside out. Flexible ductwork from the 1970s collapses, disconnects, or gets torn by rodents drawn to the moisture. We don’t patch with tape and hope; we cut out failed sections, splice in new material, and seal the joints properly.
A straightforward section replacement in Pasadena runs $300 – $600. When we need to open a slab chase or rebuild a return plenum, costs move to $500 – $900. Every repair gets a written price before we touch anything, and every repair is covered by our 365-Day Done Right Promise.
Corroded Metal Trunk Lines
Galvanized steel ducts in Pasadena homes often show pinhole corrosion where condensation pools. We section in new sheet metal, seal with mastic, and wrap with insulation where the old jacket has failed. The goal is a repair that lasts, not a patch that buys six months.
Disconnected or Collapsed Flex
Flex duct in attics sags, tears, or pulls off collars. We support it properly, replace damaged lengths with new insulated flex, and seal every connection. In Pasadena’s humidity, unsupported flex fills with water and mold; we hang it right the first time.
Trusted Brands We Service in Pasadena
We stock parts and filtration products from Honeywell, Aprilaire, and Abatement Technologies for Pasadena jobs, which means faster turnaround and no waiting on a warehouse shipment. Our equipment roster includes Rotobrush rotary brush systems for mechanical cleaning and Nikro negative-air machines for containment. When your system needs a new filter housing, a sealed return box, or upgraded filtration after we’ve sealed the leaks, we install what fits and what lasts. No hardware-store substitutions.
Common Duct Sealing Problems We See in Pasadena Homes
- Foil tape over refinery soot. Previous crews or DIY attempts used standard tape on oily duct surfaces. The film prevents adhesion, and the tape peels within weeks. We see this on at least half the Pasadena homes we inspect.
- Sweating attic ducts pulling loose. Gulf Coast humidity hits attic systems hard. Condensation forms on cool supply lines, soaks the insulation, and weighs down flex until joints separate. Sealing alone won’t fix it; we address the moisture source too.
- Slab leaks buried and invisible. Post-WWII slab homes in Pasadena often have duct chases under the foundation. A cracked collar or rusted elbow leaks conditioned air into the soil for years. Only camera inspection finds it.
- Return pan corrosion from standing water. We pulled a 1970s tract house off Richey Street where the return pan was sweating so hard the old foil tape had let go along three seams. After a negative pressure cleaning and a HEPA filtration pass, our tech degreased the trunk line with Guardsman cleaner, sealed the joints with mastic, and the supply registers stopped whistling within a day.
Pricing for Duct Sealing in Pasadena, CA
A typical whole-home duct sealing in Pasadena runs $450 – $1,200 depending on system location, accessibility, and how much prep cleaning the refinery soot requires. Attic systems with straightforward access fall at the lower end. Slab chases, buried runs needing camera inspection, or systems with extensive corrosion repair push toward the higher range.
What affects your price: the number of accessible joints, whether we need to cut access panels, the condition of existing duct material, and whether degreasing is required before mastic will bond. We do not price per vent. One flat price per system, agreed in writing, before any work starts.
Every estimate is free. Call (361) 326-5060 and we’ll schedule a look.
We Also Serve Cities Near Pasadena
Our crews work throughout the San Gabriel Valley. We regularly schedule Duct Sealing in Pasadena and surrounding communities including San Marino, South Pasadena, Altadena, and San Gabriel. The same written pricing, the same 365-Day Done Right Promise, the same prep-and-seal discipline applies in every city we serve.
Serving Pasadena, CA - Our Local Coverage Area
We’re based in the Pasadena 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 Pasadena
The refinery emissions and diesel particulate along the Ship Channel leave a fine oily soot on duct surfaces that acts as a release agent. Mastic and tape won’t bond to it. We degrease with Guardsman cleaner first, then seal. Call (361) 326-5060 if you want us to inspect whether your system has this film.
Most leaks in Pasadena homes are in attic flex connections, at the return plenum, or in slab-embedded chases where a camera is the only way to find them. Post-WWII ranches with original ductwork are especially prone to hidden breaches. We scope buried lines and pressure-test accessible systems to locate every leak before we quote.
High humidity makes attic ducts sweat, which rots insulation, corrodes metal, and loosens tape. Sealed joints in a damp environment need proper support and insulation, not just mastic. We address the moisture conditions that caused the failure so the repair lasts.
Given the refinery soot loading and humidity, every three to five years is prudent for Pasadena homes. If your energy bill spiked, rooms won’t balance, or you hear whistling, check sooner. We include a basic leak inspection with every duct cleaning service.
Yes, whistling usually means air is escaping through gaps around the register boot or the duct joint behind the wall. After we seal and balance the system, the whistling stops. If the register itself is undersized, we’ll tell you that too. Call (361) 326-5060 for an exact diagnosis.
Ready to stop losing conditioned air into your attic or under your slab? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free estimate on duct sealing in Pasadena. We’ll give you a written price before any work starts, and our 365-Day Done Right Promise covers every sealed joint for a full year.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Pasadena and the San Gabriel Valley since 2004.