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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Before
AfterFast, Reliable Duct Sealing Across Novato
Duct sealing in Novato typically runs $450 – $1,200 for a whole-house system, with most ranch-style homes in Hamilton and Pleasant Valley falling in the $600 – $900 range. We’re Hollis Air Duct Cleaning, part of the Garrison Partners family, and our crews serve Novato from our San Francisco Bay Area dispatch office. If your registers blow dust right after cleaning, or your utility bills spike every summer, you likely have leaky ductwork. Call us at (361) 326-5060 for a written estimate before any work starts.
Novato’s mix of mid-century housing, rural properties on unpaved lanes, and that distinctive dual-system setup, furnace plus whole-house fan, means duct sealing here isn’t a copy-paste job. We’ve worked on enough Hamilton ranches and Pleasant Valley spreads to know where the leaks hide and why they keep coming back.
Why Hollis Air Duct Cleaning Is Novato’s Preferred Duct Sealing Company
We’ve been in business since 2004, and our 365-Day Done Right Promise applies to every duct sealing job in Novato. The price is written down before we touch your system. If the seal fails within a year, we come back and make it right at no charge, including a free second visit.
Our technicians are background-checked and uniformed, and they arrive inside the quoted window. That’s The Garrison Standard, and it’s how every Hollis location operates, including the crews serving Novato. Phones are answered by a live person 24 hours a day, seven days a week. No voicemail loops. No waiting until Monday.
We use professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, the same tools commercial crews use. For filtration and sealing products, we stock Honeywell, Aprilaire, and Guardsman components. We don’t show up with hardware-store gear.
Duct Repair in Novato
Duct Repair in Novato usually means fixing separated galvanized trunk lines, patching corroded takeoffs, or replacing collapsed flex duct in crawl spaces that have taken on moisture. Most Novato homes built between 1950 and 1980 have original galvanized steel ductwork. Decades of thermal expansion, plus the seasonal wet-dry cycle here, loosen joints and crack seams. A typical duct repair in Novato runs $180 – $450 for localized fixes, or $600 – $1,200 if we’re rebuilding a significant section of trunk line.
Galvanized Steel Restoration
Original steel ducts in Hamilton and Pleasant Valley ranch homes often have pinhole corrosion at the seams. We cut out the damaged section, fabricate a replacement from matching gauge metal, and seal with mastic and mesh tape. Not duct tape. Mastic. It flexes with temperature swings and stays bonded for years.
Crawl Space Moisture Damage
Novato’s wet winters saturate crawl space insulation. We remove waterlogged duct wrap, repair the underlying metal, then re-insulate with proper vapor-barrier sleeve. Skipping the insulation replacement means the musty odor returns with the next rain.
Air Duct Sealing in Novato
Air Duct Sealing in Novato addresses the conditioned air you’re paying to heat or cool that escapes into your attic, crawl space, or walls before it reaches your rooms. In a typical Novato ranch home with original ductwork, 20 – 30% of airflow leaks out through loose joints and failed seams. Our air duct sealing process pressurizes the system, measures leakage with a duct blaster, then seals every accessible joint with mastic and mesh reinforcement. Typical cost: $600 – $1,200 for a whole-house seal, depending on system accessibility and whether we need to pull down wet insulation first.
Leak Detection and Measurement
We start every air duct sealing job with a pressure test. The duct blaster tells us exactly how much air is escaping and helps us locate the worst leaks. In Novato’s older homes, the biggest losses are usually at the furnace plenum and the long trunk runs feeding distant rooms or outbuildings.
Outbuilding and Shop Integration
Many rural Novato properties duct heat to detached shops or barns off the same furnace. Those long runs have more joints, more expansion stress, and more opportunities for leakage. We isolate each building’s takeoffs, seal them independently, and re-balance airflow so the house doesn’t starve while the shop gets over-pressurized.
Trusted Brands We Service in Novato
We stock parts and sealing materials from Rotobrush, Nikro, and Abatement Technologies for fast turnaround on Novato jobs. For filtration and final air-quality components, we carry Honeywell, Aprilaire, and Guardsman products. That means no waiting on a parts run to San Rafael when your system needs a new collar, a sealed transition, or a properly rated filter after we’re done. Our van inventory covers the common failure points we see in Novato’s mid-century housing stock, from galvanized flex transitions to properly sized return-air plenums.
Common Duct Sealing Problems We See in Novato Homes
- Dual-system contamination. In Pleasant Valley and the rural fringes of Novato, many properties run a forced-air furnace plus a separate whole-house fan drawing from oak woodland and wetland air, and outbuildings are frequently on the same ducted system, so a duct-sealing diagnosis has to isolate which system and which building is actually leaking.
- Gravel-road dust loading. Properties on unpaved lanes near the oak woodlands see continuous fine dust and pollen infiltration. Sealing ducts without first removing that debris means the new sealant gets blamed when dust keeps blowing.
- Fall crawl space saturation. After the first heavy rains in late fall, technicians often find that ducts in older Novato homes emit a musty odor because water seeps into crawl spaces and saturates the duct insulation, a problem less common in drier inland areas.
- Outbuilding trunk failures. The long galvanized runs serving detached shops and barns experience more thermal cycling and joint separation than house-only systems, but they’re often ignored because they’re harder to access.
Pricing for Duct Sealing in Novato, CA
A typical duct sealing job in Novato runs $600 – $1,200 for a whole-house system. Smaller homes with accessible crawl spaces might land at $450 – $650. Larger rural properties with outbuilding runs, wet insulation replacement, or extensive galvanized restoration can reach $1,000 – $1,500.
What moves the price: how much of the ductwork is accessible, whether we need to remove waterlogged insulation first, if outbuilding lines require separate sealing and balancing, and whether the system needs source removal before sealing. We give you one flat price per system, agreed in writing, before any work starts. No per-vent pricing. No invoice that grows once the van is in your driveway. Call (361) 326-5060 for a free estimate.
We Also Serve Cities Near Novato
Our crews regularly work in Novato and the surrounding communities, including Fairfax, San Anselmo, Petaluma, and San Rafael. Scheduling is coordinated from our San Francisco Bay Area office, with local technicians dispatched to each job. If you’re in one of these nearby cities and dealing with leaky ductwork, the same pricing structure and 365-Day Done Right Promise apply.
Serving Novato, CA - Our Local Coverage Area
We’re based in the Novato 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 Novato
Every three to five years for properties on unpaved lanes, because dust and pollen loading is continuous and can gradually degrade sealant at joints. After our initial sealing, we’ll note the access points and schedule a pressure-test recheck if you notice dust returning or rooms heating unevenly. Call (361) 326-5060 to book a recheck.
Yes. The whole-house fan pulls unfiltered outdoor air through separate intake pathways, and if those ducts share any junction with your furnace system, you’ve got two distinct contamination sources. We seal the furnace ducts for conditioned-air leakage and inspect any shared pathways for cross-flow. The dual-system setup is common in Novato’s ranch-style homes and requires a more careful diagnosis than a furnace-only system.
The first heavy rains saturate crawl space insulation that dried out over summer, and that moisture transfers to your duct wrap and any standing debris inside the runs. The smell releases when you fire the furnace. We see this pattern every fall in Novato’s older homes. Proper sealing includes removing wet insulation, drying the crawl space, and re-wrapping with vapor-barrier sleeve, not just slapping mastic on joints.
We seal any ductwork on your forced-air system, including outbuilding runs. In fact, those long lines often leak the most because they have more joints and experience greater temperature swing. We were out on a ranch-style Pleasant Valley property off a gravel-and-dirt drive where the shop building shares the same furnace as the house; the owner called about dust reappearing on registers days after cleaning. Using camera inspection from the air handler, we traced two failed galvanized trunk takeoffs feeding the shop, sealed them with mastic and mesh tape, then re-balanced supply and return ducts, and the dust loading on the house registers dropped noticeably.
Yes, if it’s done with the right materials and prep. Mastic stays flexible in our temperature range and bonds through moisture cycles. The failure we see isn’t the sealant degrading; it’s new water intrusion from saturated crawl spaces or skipped insulation replacement. We warranty our sealing work for 365 days under our Done Right Promise, and we specifically check for moisture issues that would undermine the seal.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Novato and the Bay Area since 2004.