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 Chatsworth
If your Chatsworth home has ducts that predate the first moon landing, you’re likely losing conditioned air through seams and joints that have quietly opened over 50 or 60 years. Duct sealing in Chatsworth typically runs $950 – $2,400 depending on how much of the system is accessible, and the work usually takes half a day to a full day. Our crews serve Chatsworth regularly, we know the ranch homes on Lassen Street as well as the custom estates up in the hills, and we’re one call away at (661) 523-0295.
Why Hollis Air Duct Santa Clarita Is Chatsworth’s Preferred Duct Sealing Company
We’ve worked on enough mid-century ranches in Chatsworth to know exactly what we’ll find when we pull a supply register off the wall: original metal ducts with gap-toothed seams, a layer of dust that’s been baking in 130°F attic heat for decades, and a homeowner who’s tired of wiping fine brown powder off the furniture every three days. Every Hollis technician is background-checked, uniformed, and trained on professional-grade equipment from Rotobrush and Nikro. We arrive inside the quoted window, put the price in writing before any work starts, and leave the site clean. That’s The Garrison Code, and it applies to every Chatsworth job.
Our owner, Roy Castellanos, holds every Hollis location to one standard: written prices, written guarantees, and a crew that shows up squared away. The 365-Day Done Right Promise backs every duct sealing job in writing. If a sealed seam opens up or a section of insulation sags within a year, we come back to Chatsworth at no charge and fix it. That’s a promise most duct cleaning outfits won’t put on paper.
Styles & brands we work with




Duct Sealing Services in Chatsworth
Duct Sealing Services in Chatsworth mean finding and closing every gap, seam, and joint where conditioned air escapes into the attic or crawlspace before it reaches your bedrooms. Air that leaks into a Chatsworth attic in August is air you paid to cool and never felt. After we seal the accessible supply and return runs with mastic and appropriate mechanical fasteners, the system moves more air to the rooms that need it. Most Chatsworth homes need sealing because the original 1950s – 70s ductwork was never designed to be airtight, and five or six decades of expansion and contraction have opened the seams.
This page covers the full Duct Sealing process we use across the San Fernando Valley. For Chatsworth specifically, the job almost always starts with source removal, not sealing. We’ll explain why in the section below. Expect $950 – $2,400 for a typical Chatsworth ranch, with larger custom estates in the hills running higher due to longer runs and zoned systems.
Source Removal Before Sealing
In most San Fernando Valley cities, you can seal duct leaks without deep-cleaning the system first. Chatsworth is different, and we’ll state it plainly: sealing leaks while leaving a baked-on crust of dust inside the ducts does nothing for the air you breathe. We remove that crust with HEPA-filtered negative-air machines before any mastic goes on. That’s the step generic duct sealing advice skips.

Mastic and Mechanical Sealing
We seal accessible seams with mastic, not cheap foil tape. Chatsworth attics regularly exceed 130°F in summer, and foil tape adhesive dries out, cracks, and falls off within a season. Mastic brushes on wet, cures hard, and stays put. Where ducts run through crawlspaces or tight soffits, we use the right mechanical method for the access we have.

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 Chatsworth
Duct Insulation in Chatsworth is the second half of what your attic ductwork actually needs. Many original ranch homes here have uninsulated or lightly insulated metal ducts running through attics that hit 130°F or more from June through September. Cooling air moving through those ducts picks up heat before it reaches the register, so your AC works harder and your far bedrooms stay warm. After we seal the leaks, we wrap accessible hot-attic supply runs with insulation rated for the temperatures we actually see up there. Expect $600 – $1,800 for insulation work depending on how many linear feet of duct are accessible.
Attic Runs and Cooling Loss
An uninsulated supply duct in a Chatsworth attic can lose 10 to 20 degrees of cooling before the air reaches the room. That’s not a guess, it’s what we measure with an infrared thermometer on a July afternoon. Wrapping those runs keeps the cold air cold and takes load off the compressor.
Insulation After Sealing
Insulation goes on after sealing, never before. Sealing first locks the conditioned air inside the duct. Insulation second keeps the heat out. Doing it in reverse wastes material and hides leaks that should have been closed. We do it in that order on every Chatsworth job.
Trusted Brands We Service in Chatsworth
We work on whatever’s in your attic, but we’re partial to equipment that’s built for commercial-style cleaning and filtration. Our Chatsworth crews run Rotobrush rotary brush systems for mechanical agitation, Nikro negative-air machines for HEPA-filtered source removal, and filtration products from Aprilaire and Guardsman where a home needs better media filtration. These are the same tools commercial crews use on hospitals and cleanrooms, and we explain what each one does for your system before we start. If a part needs replacing, we carry common sizes on the truck and can source Chatsworth-specific fittings fast.
See the difference
Before
After
Before
After
Before
AfterCommon Duct Sealing Problems We See in Chatsworth Homes
- Sealing leaks before removing baked-on dust. Original 1950s – 70s metal ducts in Chatsworth attics develop a hard crust from decades of Santa Ana dust and extreme heat. Seal the seams without removing that crust, and the source of airborne particles stays right where it was.
- Foil tape that fails in hot attics. Chatsworth attics hit 130°F or more in summer. Cheap foil tape adhesive dries out and releases within one season, reopening the gaps. We use mastic for a reason.
- Static pressure spikes after sealing. Sealing ducts on an older ranch raises static pressure in the system. If the blower motor and air handler are caked with years of Santa Susana dust, that added pressure can overload the motor. We check and clean the blower as part of sealing work.
- Ignoring the return side. Most Chatsworth homes have more leaks on the return side than the supply side. Return leaks pull attic air, dust, and heat into the system before it ever reaches the filter. Sealing supply runs alone leaves half the problem untouched.
Pricing for Duct Sealing in Chatsworth, CA
A typical duct sealing job in Chatsworth runs $950 – $2,400. The range depends on how much of the duct system is accessible from the attic or crawlspace, how many linear feet of seams need mastic, and whether the system requires source removal first, which most original Chatsworth systems do. Duct insulation adds $600 – $1,800 depending on linear footage. Larger custom estates in the hills with zoned systems run higher. We give you a written price before any work starts, and that price does not move at the door. Call (661) 523-0295 for a free estimate; we’ll schedule a time that works for you, show up inside the window, and tell you exactly what the job costs before we touch anything.
We Also Serve Cities Near Chatsworth
Our crews cover the northwest Valley and surrounding areas. You’ll find us regularly in Duct Sealing in Chatsworth, plus Porter Ranch, Northridge, Canoga Park, and Reseda. If you’re a few blocks outside Chatsworth proper, call and ask; we’ll likely be in your neighborhood this week anyway.
Serving Chatsworth, CA - Our Local Coverage Area
We’re based in the Chatsworth 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 Chatsworth
Santa Susana dust is fine, mineral-heavy, and relentless, and Chatsworth’s Santa Ana winds push it into homes and duct systems faster than in the cooler, flatter parts of the Valley. That dust settles inside ducts, and the intense attic heat bakes it into a hardened crust on duct walls. Sealing leaks without removing that crust first leaves the source of airborne particles in place, which is why our Chatsworth process always starts with source removal.
You don’t strictly need insulation if you’re only sealing leaks, but most Chatsworth ranchers with original attic ductwork benefit from both. Sealing stops conditioned air from escaping. Insulation stops attic heat from warming the air that stays inside. On a 105°F Chatsworth afternoon, uninsulated ducts can lose 10 to 20 degrees of cooling before the air reaches the register. We quote sealing and insulation separately so you know exactly what each costs, and you decide. Call (661) 523-0295 for a written estimate.
If the previous company used foil tape, that’s your answer. Chatsworth attics exceed 130°F in summer, and foil tape adhesive dries out and releases within one season. The gaps reopen. If they sealed leaks without removing the baked-on dust first, the system may also be overloaded with static pressure from air now pushing against clogged sections. We use mastic on seams, check the blower motor and air handler, and back the work in writing with the 365-Day Done Right Promise.
Sealing alone only stops attic air from being pulled into the ducts through gaps and open seams. If the dust is already inside the ducts in the form of a baked-on crust, sealing the leaks won’t remove it. That’s why our Chatsworth process combines source removal with sealing and, where needed, insulation. A camera inspection shows us exactly where the dust is and where the leaks are before we start. Call (661) 523-0295 to schedule one.
A camera inspection shows us three things: where the leaks are, how much baked-on dust has accumulated, and whether the ducts are original metal or replaced. In a 1960s ranch on Lassen Street, our camera found multiple small gaps at the seams and a dust crust so hard from years of attic heat that standard agitation couldn’t break it loose. That inspection told us exactly what the job needed: source removal with HEPA filtration, mastic sealing on the accessible leaks, and insulation on the hot attic runs. Without the camera, we’d be guessing. We don’t guess.
Written by Roy Castellanos, Owner at Hollis Air Duct Santa Clarita, serving Chatsworth and the northwest San Fernando Valley.