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 South San Jose Hills
Duct sealing in South San Jose Hills typically runs $1,200 – $2,800 for a whole-home system and takes one full day to complete properly. Most homes here are mid-century ranches with original ductwork that’s never been sealed, so the work often uncovers leaks at returns pulling air from garages and crawlspaces.
We’re Hollis Air Duct Cleaning, and we’ve worked on enough houses off Valley Boulevard and around the Puente Hills to know what these 1950s – 1970s ranch systems look like before we open the attic hatch. Dispatch and scheduling are coordinated from our Los Angeles office, but our crews serve South San Jose Hills directly. We arrive inside the quoted window, price the job in writing before touching anything, and leave the site clean. That’s The Garrison Standard. Call (361) 326-5060 for a free estimate.
Why Hollis Air Duct Cleaning Is South San Jose Hills’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and our track record predates most competitors you’ll find advertising in South San Jose Hills. Homeowners here aren’t looking for the cheapest coupon; they’re looking for a crew that shows up uniformed, background-checked, and ready to explain what they found in plain terms.
Our technicians carry Rotobrush rotary brush systems and Nikro negative-air machines, the same tools commercial crews use. Every job gets a written price before work starts, and every repair is covered by our 365-Day Done Right Promise. If the work fails within a year, we come back and make it right at no charge, including a free second visit.
Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No callback queues.
Duct Insulation in South San Jose Hills
Duct Insulation in South San Jose Hills addresses a specific problem: the original fiberglass wrap on mid-century ranch ductwork has compressed, torn, or fallen away entirely, leaving metal or early flex ducts exposed to attic temperatures that hit 140°F in July and August. When your cooled air travels through uninsulated ductwork in a low-pitch attic, you lose 20 – 30% of your conditioning before it reaches the register. A typical duct insulation job in South San Jose Hills runs $800 – $1,800 depending on linear footage and accessibility.
When Insulation Matters More Than Sealing
Some South San Jose Hills homes have tight joints but bare metal. In these cases, adding closed-cell foam or fiberglass wrap with a vapor barrier does more good than chasing phantom leaks. We inspect first, recommend second.
Attic Access Challenges on Low-Pitch Ranches
Many South San Jose Hills attics are shallow crawlspaces with a single scuttle hole. Our crews carry portable lighting and compact equipment specifically for these conditions. If we can’t move safely, we don’t move at all. We’ll tell you upfront.
HVAC Duct Sealing in South San Jose Hills
HVAC Duct Sealing in South San Jose Hills is rarely a simple matter of taping a few visible trunk joints. Because most homes here are unincorporated mid-century single-story ranches, a large share of duct-sealing work happens at the return. Many systems were originally tied to crawlspace or garage air rather than a conditioned hallway, so sealing a “duct” here often means correcting an intake that was never really part of the house envelope. In neighboring Rowland Heights and Walnut, where the housing stock skews newer custom build, that garage/crawlspace return condition is far rarer, so the diagnostic sequence and the fix are different from the start. A typical HVAC duct sealing job in South San Jose Hills runs $1,200 – $2,800.
The Return-Side Problem
On a ranch off Valley Boulevard backing toward the Puente Hills, our tech camera-inspected a 1968 single-story with one original furnace system and found the return boot in the garage drawing fine dust straight off an unpaved lot next door. We staged the work under negative pressure with HEPA filtration, used agitation tools to break loose the packed silt in the supply and return ducts, then sealed the leaking trunk joints, the garage return connection, and the plenum at the air handler with mastic and mesh. The homeowner’s complaint – gritty dust settling on furniture within a day of running the blower motor – stopped within the first cooling cycle, and the blower motor amp draw dropped because it was no longer pulling against an open garage.
Mastic and Mesh vs. Tape-Only Repairs
Tape fails. The Santa Ana winds cycle hot air through South San Jose Hills attics, metal expands and contracts, and adhesive gives up. We use water-based duct mastic reinforced with fiberglass mesh on every joint. It’s slower. It lasts.
Trusted Brands We Service in South San Jose Hills
Our equipment roster includes Rotobrush rotary brush systems for mechanical agitation, Nikro negative-air machines for controlled debris extraction, and filtration products from Aprilaire and Abatement Technologies. We stock common plenum fittings, collar connectors, and mastic supplies for South San Jose Hills jobs, so we’re not waiting on a parts run to Los Angeles while your attic is open. Most repairs finish in one day. If we need a specialty component for an older system, we’ll tell you before we start, with a clear timeline.
Common Duct Sealing Problems We See in South San Jose Hills Homes
- Garage and crawlspace returns pulling unfiltered outside air. Many South San Jose Hills ranches were built with return ducts drawing from the garage or a dirt-floored crawlspace. Sealing only the supply trunk and leaving this return path open wastes money and circulates dust from horse properties and unpaved lots.
- Tape-only patches on original galvanized duct. Previous owners or handymen often wrapped leaking joints with foil tape. The first hot Santa Ana wind cycle loosens the adhesive. We remove the tape, clean the metal, and apply mastic with mesh.
- Undersized filtration allowing fine silt to load the coil and motor. Even perfectly sealed ducts won’t help if the return is pulling Puente Hills debris through a 1-inch throwaway filter. We check filter sizing and MERV rating as part of every sealing evaluation.
- Collapsed or disconnected flex duct in low-pitch attics. Original flex duct from the 1970s has often sagged, torn at the collar, or pulled completely off the boot. These aren’t leaks; they’re open bypasses. We document each find with photos before repair.
Pricing for Duct Sealing in South San Jose Hills, CA
A typical whole-home duct sealing in South San Jose Hills runs $1,200 – $2,800. Single-system ranches at the lower end. Homes with two or three systems, or those requiring return reconstruction from a garage or crawlspace, run higher. We price per system, not per vent, so a house with three HVAC units gets three written quotes you can approve or decline independently.
What moves the number: linear footage of ductwork, accessibility of the attic or crawlspace, whether returns need rerouting from garage/crawlspace to conditioned space, and if we find collapsed flex or rodent damage requiring section replacement. We inspect with a camera first. You see what we see. The price is written down before any work starts, and it does not move at the door.
Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near South San Jose Hills
Our crews travel throughout the region for Duct Sealing in South San Jose Hills and surrounding communities, including Los Angeles, San Diego, San Jose, and San Francisco. Each Hollis location is independently owned and operated under The Garrison Standard, so you’re working with a local crew accountable to your neighborhood, not a distant call center. For details on our full service approach, visit our Duct Sealing hub page.
Serving South San Jose Hills, CA - Our Local Coverage Area
We’re based in the South San Jose 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 South San Jose Hills
Because most South San Jose Hills ranches were built with returns drawing from garages or crawlspaces rather than conditioned hallways, the return path is often the largest unsealed opening in the system. Sealing supply joints helps, but leaving a garage return open means you’re filtering outside air through your living space. We camera-inspect both sides before quoting. Call (361) 326-5060 for a free evaluation.
Most galvanized duct from this era can be sealed if the metal is structurally sound. We check for rust-through, collapsed sections, and separated collars. Where the metal is intact, mastic and mesh sealing restores performance at a fraction of replacement cost. If sections are too far gone, we’ll show you the camera footage and quote replacement separately. Call (361) 326-5060 to schedule an inspection.
We provide before-and-after photos from our borescope camera, a written work summary listing every joint and return that was sealed, and pressure-differential readings where applicable. The 365-Day Done Right Promise backs it in writing: if the work fails within a year, we return at no charge. Documentation is your proof; our guarantee is our accountability.
Yes, but only if the return side is included. The Santa Ana winds drive fine silt through any opening. If your return is pulling from a garage or crawlspace, sealing supply joints alone won’t stop it. Our South San Jose Hills protocol includes return evaluation, filtration sizing, and sealing the envelope path, not just the duct joints. The Valley Boulevard ranch we worked on saw dust settlement stop within one cooling cycle after full return sealing.
Per system. Each HVAC unit has its own duct network, attic access point, and return configuration. We inspect and quote each independently so you’re not paying for systems that don’t need work. A single-system ranch in South San Jose Hills typically runs $1,200 – $1,800. Two-system homes run $2,000 – $2,800. Three systems are quoted after inspection. Every price is written and approved before work begins. Call (361) 326-5060 for your specific layout.
Ready to stop losing conditioned air to your attic and garage? Call Hollis Air Duct Cleaning at (361) 326-5060 for a free, written estimate on duct sealing in South San Jose Hills. We’ll camera-inspect your system, show you what we find, and price the work before we start. Every job carries our 365-Day Done Right Promise, backed in writing.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving South San Jose Hills under The Garrison Standard.