Duct Sealing in Corte Madera - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Corte Madera

Duct sealing in Corte Madera typically runs $1,200 – $2,800 for a whole-home system, with most jobs completed in a single day and priced in writing before we start. If your vents blow dusty air, your energy bills keep climbing, or you smell smoke after Marin hill wildfires, the culprit is often leaky duct joints pulling unfiltered outside air into your system. For related maintenance, see our Corte Madera Dryer Vent Cleaning service.

Call (361) 326-5060

We’re the Duct Sealing in Corte Madera crew that shows up uniformed, background-checked, and on time. Dispatch and scheduling are coordinated from our San Francisco Bay Area office, but our trucks serve Corte Madera neighborhoods directly. We know the Christmas Tree Hill crawlspaces, the Chapman Park ranches, and the way Tamalpais Valley fog works its way into galvanized ductwork. Call (361) 326-5060 for a free estimate.

Why Hollis Air Duct Cleaning Is Corte Madera’s Preferred Duct Sealing Company

We’ve been part of the Garrison Partners family since 2004, and our Corte Madera customers come back because we do what we said we’d do. Our technicians arrive inside the quoted window, price the job in writing before touching anything, and leave the site clean. That’s The Garrison Standard, not a slogan.

Our 365-Day Done Right Promise covers every duct sealing job in writing. If the seal fails within a year, we return and make it right at no charge, including a free second visit. No negotiation, no runaround.

Phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday morning to schedule.

Our crew knows Corte Madera’s housing stock. We’ve crawled through enough mid-century ranch crawlspaces to spot the difference between a duct that needs sealing and one that’s too corroded to save. That local knowledge saves homeowners money and prevents callbacks.

Duct Insulation in Corte Madera

Duct Insulation in Corte Madera addresses a problem most homeowners don’t know they have: cold, unconditioned air surrounding their ductwork in damp crawlspaces and attics, forcing the HVAC system to work harder and driving up Pacific Gas & Electric bills. In Corte Madera’s fog-belt climate, where marine moisture funnels through the Corte Madera Creek gap, uninsulated ducts in vented crawlspaces lose up to 30% of their conditioned air before it reaches the vent. We typically see this in 1950s and 1960s ranch homes in Christmas Tree Hill and Chapman Park, where original installations skipped insulation to save on upfront costs.

A typical duct insulation job in Corte Madera runs $800 – $1,800 depending on linear footage and accessibility. We use formaldehyde-free fiberglass duct wrap or closed-cell foam insulation, secured with mechanical fasteners and sealed at all seams. The price is written down before we start.

When Insulation Matters More Than Sealing Alone

Some Corte Madera homes have tight duct joints but no insulation at all. The system leaks energy through the metal walls themselves. In these cases, sealing without insulating solves only half the problem. We inspect with a borescope camera to determine whether your ducts need one, the other, or both.

Fog-Zone Crawlspace Considerations

Corte Madera’s overnight temperatures drop below the dew point for much of the year. Uninsulated ducts sweat on the outside, dripping condensation onto crawlspace floors and promoting mold growth. Proper insulation with a vapor barrier breaks this cycle.

HVAC Duct Sealing in Corte Madera

HVAC Duct Sealing in Corte Madera fixes the leaks, gaps, and disconnected joints that pull unfiltered outside air into your heating and cooling system. In our market, the most common failure points are plenum seams, trunk-to-branch connections, and the spots where galvanized supply lines pass through crawlspace walls. A typical whole-home HVAC duct sealing job in Corte Madera costs $1,200 – $2,800, with larger homes or complex crawlspace runs toward the higher end. We price by the system, not by the vent, and that price is locked before work begins.

Our Duct Sealing process starts with a camera inspection of the full duct network. We pressurize the system to identify leak locations, then seal accessible joints with mastic and reinforced mesh tape. For buried or inaccessible runs, we evaluate whether aeroseal application is appropriate. Every step is documented with before-and-after photos for the homeowner.

Mastic vs. Tape: What Lasts in Corte Madera’s Climate

We don’t use foil tape as a primary sealant on Corte Madera jobs. The temperature swing between wet winter fog and dry summer heat cycles the adhesive until it fails. Water-based duct mastic, reinforced with fiberglass mesh tape, flexes with the metal and maintains its bond through decades of seasonal change.

Camera Inspection Before Sealing

Skipping this step is how technicians miss crushed branch lines or disconnected returns hidden behind crawlspace insulation. We inspect first, seal second, and show the homeowner the footage. No guesswork, no sealing over symptoms while the real leak persists.

Trusted Brands We Service in Corte Madera

Our trucks carry professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, plus filtration and sealing products from Honeywell, Aprilaire, and Guardsman. We don’t run to the hardware store mid-job. For Corte Madera homeowners, that means faster turnaround and no delays waiting on parts. Our rotary brush systems and negative-air machines are the same tools commercial crews use in hospitals and schools, maintained on a strict schedule and operated by technicians trained on The Garrison Code. When we seal your ducts, we use Guardsman-rated mastic compounds formulated for the temperature and humidity swings of coastal Marin County.

Common Duct Sealing Problems We See in Corte Madera Homes

• Fog-driven condensation corroding galvanized ductwork from the outside in. Corte Madera’s position at the bottom of the Tamalpais Valley means marine fog funnels through the Corte Madera Creek gap and keeps overnight duct-surface temperatures below the dew point for much of the year. Unsealed galvanized supply runs in mid-century ranch crawlspaces sweat and corrode, weakening joints and creating new leak paths even where the original installation was tight.
• Wildfire smoke intrusion through leaky plenum seams and crawlspace penetrations. After major fire events in the Marin hills, we see a surge of calls from Corte Madera homeowners who smell smoke from their vents. The culprit is usually daylight-visible gaps at the plenum or around duct penetrations into the crawlspace, pulling outside air directly into the return side of the system.
• Failed foil tape from temperature cycling. Previous owners or handymen often sealed ducts with hardware-store foil tape. One season of fog-cycle swelling and fire-season drying, and the adhesive releases. We remove the old tape, clean the metal, and seal with mastic that won’t degrade.
• Crushed or disconnected branch lines hidden in crawlspace insulation. Mid-century ranch builders in neighborhoods like Christmas Tree Hill sometimes ran flexible branch ducts through tight crawlspaces where they got stepped on, kinked, or pulled loose by rodents. A camera inspection finds these before we seal, so we don’t just trap the leak behind a new layer of mastic.

Pricing for Duct Sealing in Corte Madera, CA

We Also Serve Cities Near Corte Madera

Our crews work throughout central Marin County, including Corte Madera, Larkspur, Mill Valley, Kentfield, and San Rafael. Each community has its own housing stock and climate quirks, and we adjust our approach accordingly. The fog-belt condensation issues we see in Corte Madera are less severe in inland San Rafael, while Mill Valley’s steeper hillsides present different crawlspace access challenges.

FAQs About Duct Sealing in Corte Madera