Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-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 Altadena
Duct sealing in Altadena usually runs $850 – $1,600 for a typical single-family home, depending on how much of the existing ductwork can be saved and how much needs to be reconnected or replaced. Most jobs take one day, and the real cost driver here is age: homes built between 1920 and 1970 often have original galvanized steel runs that have corroded at the seams, separated at the joints, or been crushed in crawlspaces. We work those problems every week. If you’re in Altadena and your registers blow weak, your rooms heat unevenly, or you’re seeing dust reappear days after cleaning, call us at (626) 469-5477. We’ll put eyes on it with a camera inspection, write the price down before we touch anything, and stand behind the work for a full year.
Why Hollis Air Duct Pasadena Is Altadena’s Preferred Duct Sealing Company
Altadena homeowners call us because the houses here have a specific set of problems, and we’ve seen all of them. The 1920s Craftsman bungalows off Lake Avenue have crawlspace ducts that have been settling for decades. The mid-century ranches up toward Farnsworth Park have galvanized supply runs rusting through at the seams. The 1970s builds along Altadena Drive have return plenums that were never sealed properly in the first place. We don’t walk in with a sales script; we walk in with a camera and a written price.
We’re part of the Garrison Partners family, founded in 2004, and we run every job to The Garrison Standard. That means the technician arrives inside the quoted window, in a uniform, with a background check already on file. The price is written down before any work starts, and it does not move at the door. If the seal fails within a year, the 365-Day Done Right Promise brings us back at no charge. That’s not a verbal assurance. It’s in writing on every job, including every duct sealing job in Altadena.
Roy Castellanos leads our crew. He’s the one who set the expectation that we answer the phone with a live person, 24/7, and that we don’t leave a job until the crawlspace is cleaner than we found it. That’s what keeps Altadena homeowners calling us back.
Styles & brands we work with
Air Duct Sealing in Altadena
Air Duct Sealing in Altadena is the difference between cleaning a duct system and actually fixing it. A cleaning removes what’s inside the ducts. Sealing closes the leaks that let dust, ash, and crawlspace air back in. In Altadena, where the housing stock runs from 1920s Craftsman to 1970s ranch, sealing usually involves more than brushing mastic over a few joints. We’re often reconnecting runs that have separated, replacing sections that have rusted through, and sealing off returns that are pulling unconditioned air from the crawlspace.
What a Real Seal Covers
We seal every accessible joint, seam, and plenum connection with duct mastic, the fiber-reinforced paste that actually bonds to galvanized metal. Foil tape doesn’t hold here; the Santa Ana cycles of heat and dry air cause it to lift within a season. Mastic, applied correctly, stays. We also check the boot connections at every register, because a gap there sends conditioned air into the wall cavity instead of the room.
When Altadena Homeowners Need It
You need sealing when the system is leaking more than about 15 percent of the air it moves. The signs are specific: rooms that never reach the thermostat setting, dust building up on registers within a week, and a crawlspace that smells musty and is making its way into the house. If your ducts have never been sealed since the house was built, they’re leaking. It’s not a judgment call; it’s a physics problem.
Duct Sealing Services in Altadena
Duct Sealing Services in Altadena look different depending on what the camera inspection turns up. We use the same inspection approach on every job: push a camera through the supply and return runs, document what we find, and show you the photos before we price anything. That inspection typically reveals one of three things in an Altadena home: separated joints, crushed sections, or rust-through at the seams. Sometimes all three at once.
Reconnecting and Sealing Existing Runs
When the original galvanized ducts are still holding together, the right move is often to reconnect separated sections, re-hang sagging runs, and seal every joint with mastic. This runs $850 – $1,200 for a typical single-story Altadena home. It’s the most common scope we write.
Replacing Corroded or Crushed Sections
When a section of duct has rusted through, or a return has been crushed under the hallway, sealing around it doesn’t solve the problem. The section needs to come out. That shifts the job into the $1,200 – $1,600 range, depending on how much linear footage is involved and whether the run is in a tight crawlspace or an attic. A camera inspection is how we tell the difference before we write the price.
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.
Trusted Brands We Service in Altadena
Our Duct Sealing crews run professional-grade equipment, not hardware-store gear. We use Rotobrush rotary brush systems for cleaning before sealing, Nikro negative-air machines to keep airborne dust contained during the job, and filtration products from Honeywell and Aprilaire when a home needs better air after the work is done. Because we stock common fittings and mastic locally for Altadena jobs, we don’t have to make a second trip to finish most work. The equipment matters because the seal needs to hold on old galvanized steel, and that requires the right material, applied the right way.
See the difference
Before
After
Before
After
Before
AfterCommon Duct Sealing Problems We See in Altadena Homes
- Rust-through on original galvanized runs. Homes built from the 1920s through the 1950s have ducts that are now 60 to 100 years old. In Altadena’s crawlspaces, seams rust from the inside out, and tape-on sealants flake off within a season. Mastic over a rusted seam does nothing; the metal itself has to be repaired or replaced.
- Crushed returns and supplies in tight crawlspaces. Seismic settling and the expansive soils common in the San Gabriel foothills shift ducts over decades. A return that’s been pinched under a hallway floor pulls air from the crawlspace instead of the house, and no amount of register cleaning will fix that.
- Santa Ana dust bypassing weak seals. When the winds push fine dust and ash against the house, any unsealed gap in the attic runs becomes an intake vent. We see this after every strong wind event, and it’s worse when a previous cleaning didn’t include sealing.
- Plenum connections that never fit right. On many 1970s ranch homes, the return plenum was sealed with tape at installation. After 50 years, that tape is dust. The gap at the plenum is the single biggest source of crawlspace air entering the system.
Pricing for Duct Sealing in Altadena, CA
Duct sealing in Altadena typically runs $850 to $1,600 for a single-family home, and the price is written down before any work begins. The spread comes down to what the camera inspection finds. A straightforward job on a smaller ranch with accessible crawlspace ducts lands around $850 – $1,100. A larger mid-century home with separated runs and a rusted section to replace lands closer to $1,300 – $1,600. We don’t price per vent, and we don’t advertise a teaser number that changes once we’re inside. The quote you sign is the price you pay, and the 365-Day Done Right Promise covers it in writing. Call (626) 469-5477 for a free estimate, and we’ll schedule the inspection at a time that works for you.
We Also Serve Cities Near Altadena
Beyond our regular Duct Sealing in Altadena routes, we run the same crews and the same written-price standard to Pasadena, San Gabriel, Alhambra, and Arcadia. If you’re in one of those nearby cities and dealing with the same older housing stock and foothill dust, the phone number is the same. Call (626) 469-5477.
Serving Altadena, CA - Our Local Coverage Area
We’re based in the Altadena 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 Altadena
Because the ducts themselves are failing. Homes built before 1960 in Altadena typically have original galvanized steel runs that have corroded, separated, or collapsed after six to ten decades of thermal cycling, seismic settling, and crawlspace moisture. Cleaning removes the debris but doesn’t close the gaps pulling new debris in. If a camera inspection shows separated joints or rust-through, sealing is the only fix that addresses the problem. Call (626) 469-5477 and we’ll show you the footage ourselves.
Wildfire smoke drives fine ash through any available gap into the duct system, and unsealed ducts give that ash a direct path inside. After a significant brush fire in the Angeles National Forest, we consistently see sooty buildup inside supply registers of Altadena homes, especially those with attic runs that were never sealed. If the system leaks, cleaning it once just resets the clock. Sealing it means the next smoke event can’t bypass the filter the same way. For a camera inspection, call (626) 469-5477.
In a typical 1950s or 1960s ranch in Altadena, the inspection usually shows one of three things: rust-through at the galvanized seams, separated joints where the ducts have pulled apart, or a crushed return under a hallway or living room floor. We document all of it with photos before we price the job. You’ll see exactly what we see, and we’ll explain what needs to be fixed and what can wait. That’s the only way to write an honest price for duct sealing.
Yes, assuming the air handler itself is still operating safely and moving air. Sealing the distribution system means more of the conditioned air actually reaches the rooms, even with an older furnace or AC unit. If the handler fails later, the sealed ducts are still good. If the handler is original and struggling, we’ll tell you that too and recommend an HVAC contractor before we sell you a seal. The goal is fixing the right thing, not the most expensive thing.
Cleaning alone is rarely enough after wildfire smoke because the ash that entered the system did so through gaps that are still there after the cleaning is done. Sealing closes those gaps so the next smoke event doesn’t bring the same problem back within weeks. If you’ve had a post-fire cleaning and the registers are already dirty again, the ducts are leaking. Call us at (626) 469-5477 for an inspection and a written price.
Written by Roy Castellanos, Owner at Hollis Air Duct Pasadena, serving Altadena with duct sealing, air duct cleaning, and dryer vent cleaning under The Garrison Standard since 2004.