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 Mission Hills
Duct sealing in Mission Hills usually runs from $450 to $1,100 per system, depending on how many runs need work and how tight the attic access is. Most jobs on Mission Hills estates take four to eight hours, and we quote a firm price before any work starts. If you’re losing cooled air into an attic that hits 130 degrees in August, or a far bedroom never reaches the thermostat setting, a leak in the ductwork is the most common culprit. Call (661) 523-0295 and we’ll camera-inspect the runs before we touch anything, so you see exactly what we’re sealing and why.
Mission Hills is not a one-size-fits-all service area. The housing stock here runs large: custom estates with separate wings, pool houses, guest quarters, and duct runs that stretch 40, 60, or 80 feet from the air handler. Our Duct Sealing team works these systems every week. We know that a 1970s estate off Woodley Avenue has different duct realities than a 1990s build near Sepulveda, and we price and document accordingly. This page is written for Mission Hills homeowners specifically, because what happens inside houses here is not what happens in a typical San Fernando Valley tract home.
Why Hollis Air Duct Santa Clarita Is Mission Hills’s Preferred Duct Sealing Company
Roy Castellanos leads our Mission Hills crews, and he runs every job on The Garrison Code: arrive inside the quoted window, put the price in writing before work begins, complete the job by the book, and leave the site clean. That is the entire promise, and it is written on every job ticket. Mission Hills homeowners have been calling us for years because we do not send a different crew each time and we do not quote a number that moves once the technician is in the attic.
We serve Mission Hills with background-checked, uniformed technicians who carry professional-grade equipment from Rotobrush and Nikro. The same tools commercial crews run, not something picked up at a hardware store. When we seal ducts in a Mission Hills attic, we are working in tight chases, around vaulted ceiling framing, and through crawl spaces that most companies will not enter with a camera. That is the difference between sealing a duct and actually documenting that it is sealed.
Our 365-Day Done Right Promise covers every duct sealing job in Mission Hills for a full year. If a sealed seam fails within that year, we return and make it right at no charge. That includes a free second visit, not a negotiated callback. Written price before work starts, written guarantee behind the work when it is done. No exceptions, no fine print.
Styles & brands we work with




Duct Repair in Mission Hills
Duct Repair in Mission Hills typically runs from $250 to $700, depending on how many sections of damaged ductwork need to be replaced or reconnected. On these larger estate homes, we frequently find collapsed flex runs, disconnected trunk joints, and duct tape seams that have failed inside ceiling boxes you cannot see from the living room.
- Collapsed flex runs: In Mission Hills attics, older flex duct can sag and kink between joists, strangling airflow to distant rooms. Replacement runs from $150 to $300 per section depending on length and access.
- Failed duct tape joints: Duct tape dries out within two Valley summers and releases from metal trunk lines. We remove it and seal with mastic rated for attic temperatures.
- Plenum-to-trunk separation: We see this on attic-mounted air handlers all over Mission Hills. The seam pulls apart and the system pulls 130-degree attic air into the supply side.
Leaky Trunk Lines Over Vaulted Ceilings
Mission Hills homes with vaulted ceilings often have the supply trunk running through a tight attic chase above the ceiling plane. When the trunk leaks there, you cannot see it, but you feel it: the far rooms never cool, and the blower runs long cycles. We camera-inspect those runs end to end and seal them with mastic applied from the outside, which is the correct method for metal duct.
Replacing Collapsed Flex To Pool Houses and Guest Wings
Long flex runs serving detached pool houses or guest quarters are exposed to more heat and more dust than any other part of the system. We pull and replace collapsed sections, reconnect them to the plenum properly, and wrap the joints. The result is a secondary structure that finally conditions the way it was designed to.
Air Duct Sealing in Mission Hills
Air Duct Sealing in Mission Hills runs from $450 to $1,100 per system, and on an estate with three separate HVAC systems, that means per-system pricing rather than one vague whole-house number. Sealing a system involves closing every accessible seam, joint, and small penetration so the air the blower pushes into the ducts actually reaches the register instead of leaking into unconditioned space.
Sealing Multi-Zone Estate Systems
Mission Hills custom homes commonly run two, three, or four zones with long supply trunks serving separate wings. Zone dampers that have been fouled by years of dust may stick partly open, pushing conditioned air into unused rooms and driving static pressure high enough to separate duct joints. Sealing those runs while the dampers are still accessible is part of the job. We do not just paint mastic on a seam; we check the whole airflow path.
Balancing For Undersized Return-Air Ducts
Many Mission Hills homes built from the 1960s onward have original return-air ducts that were sized too small for the system when it was installed, and certainly too small for the systems operating now. Heavy pollen from mature landscaping loads filters fast and adds resistance. When we seal a supply side that has been leaking for years, we measure static pressure before and after, because sealing done right should not make an undersized return situation worse. Sometimes the sealing work includes helping the homeowner understand what the return side needs next.
Trusted Brands We Service in Mission Hills
We work on systems and duct configurations tied to brands Mission Hills homeowners actually have in their mechanical rooms: Aprilaire filtration housings, Abatement Technologies negative-air equipment, and Guardsman purification products, along with whatever brand of air handler is already in the home. We keep sealing-compatible mastics, tapes, and replacement flex runs stocked locally, so a Mission Hills job does not wait on a warehouse shipment from across town. Whether the system is original to a 1970s estate or a recent retrofit, we seal it to the same standard.
See the difference
Before
After
Before
After
Before
AfterCommon Duct Sealing Problems We See in Mission Hills Homes
- Failed silicone and duct tape on old metal ducts. Mission Hills attics hit extreme heat every summer. Silicone caulk and duct tape dry, crack, and release within two Valley summers, opening leaks behind ceiling boxes no one can see until the registers start blowing attic dust.
- Plenum-to-trunk leaks on attic-mounted air handlers. Vaulted ceilings put the air handler in the attic, and that plenum connection carries the highest static pressure in the system. When it leaks, the supply side pulls 130-degree attic air and pushes it into the house.
- Stuck zone dampers on multi-zone systems. Dust and pollen from Mission Hills landscaping builds up on damper blades and actuators. A damper stuck partly open sends conditioned air into an empty wing, and the system runs longer trying to satisfy a thermostat it can never satisfy.
- Long flex runs to pool houses and guest quarters. Those runs are the most exposed and least inspected. They sag, kink, and collapse, and the homeowner only learns it when the pool house never cools below 85 in July.
Pricing for Duct Sealing in Mission Hills, CA
A single-system duct sealing job in Mission Hills typically lands between $450 and $1,100, depending on how many runs we document and seal, how long the trunk lines are, and whether we are replacing damaged flex sections as we go. A three-system estate, the kind with a main wing, guest house, and pool cabana, should expect between $1,200 and $3,000 total, priced per system before we touch anything. Duct repair as a standalone job runs $250 to $700. We do not quote per-vent prices and we do not run teaser coupons that balloon at the door. The price you get on the phone is the price on the work order. Call (661) 523-0295 for a free estimate.
We Also Serve Cities Near Mission Hills
Our duct sealing crews cover Mission Hills and the surrounding San Fernando Valley communities, including San Fernando, Granada Hills, Panorama City, and Sylmar. If your home is in one of those areas, the same pricing discipline, written guarantee, and camera-documented proof applies. Call (661) 523-0295 and we will schedule a time that works for you.
Serving Mission Hills, CA - Our Local Coverage Area
We’re based in the Mission Hills 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 Mission Hills
We document every job with a camera before and after. You see the leaks we found, the seams we sealed, and the runs we replaced. No other documentation approach works for ducts you cannot physically see from a living space, and we do not expect you to take our word for it. The photos go into your job record, and they are yours to keep. Call (661) 523-0295 to schedule an inspection.
Per-system pricing means each HVAC system is quoted separately, because each has its own trunk lines, its own runs, and its own condition. A three-system estate might run $1,200 to $3,000 total, but each system is priced on its visible condition before work begins, not averaged into one number. You know what each system costs and what was done to each. Call (661) 523-0295 and we will walk the systems with you.
Many Mission Hills estates were built with return-side ducting that was marginal when the home was new and is now moving more air than it was designed for. Heavy pollen from mature landscaping loads filters faster and adds resistance to the return path. Sealing the supply side correctly should not make that worse, but we measure static pressure before and after on every job, and we will tell you plainly if the return side needs attention after the leaks are sealed. Call (661) 523-0295 and we’ll explain what we find.
Sealing closes the gaps where pollen and fine dust enter the supply side from the attic, so it reduces what reaches the registers. It does not replace filtration, but a sealed system gives your filter a fighting chance by keeping the attic air out of the supply stream. On a Mission Hills estate with mature trees and hillside vegetation, that reduction is measurable in the first week. Call (661) 523-0295 and we’ll show you where the dust is entering your ducts.
We follow NADCA standards for duct system evaluation and sealing, including camera documentation and static pressure testing before and after the work. The techs verify the job by re-cameraing the sealed runs, checking the pressure readings, and confirming that the airflow at the furthest register has changed for the better. The entire verification is part of your written record. Call (661) 523-0295 to discuss a full evaluation of your Mission Hills system.
Written by the team at Hollis Air Duct Santa Clarita, serving Mission Hills with honest duct sealing and repair. Call (661) 523-0295 for a free estimate and a written price before any work begins.