Duct Sealing in Cotati - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Cotati

Duct sealing in Cotati typically runs $450 – $1,200 for a whole-home system, and most jobs are scheduled within a few days of your call. If you’re losing heated or cooled air through gaps in your ductwork, you’re paying to condition your crawlspace or attic instead of your living rooms.

Call (361) 326-5060

We know Cotati’s two faces: the tight grid of pre-WWII cottages around the downtown hexagon, where original metal ducts snake through accessible crawlspaces, and the packed subdivisions off Highway 101 in Rancho Cotate, where builder-grade flex duct from the 1980s and 1990s is starting to sag at the seams. Both leak. Both waste money. Both get worse every season that coastal fog and pollen work their way into the joints. Our Duct Sealing in Cotati crews coordinate scheduling from our San Francisco Bay Area office and roll to Cotati with mastic, metal tape, and replacement fittings sized for what we find here. Call (361) 326-5060 and we’ll walk through what you’re seeing, or not seeing, on your utility bills.

Why Hollis Air Duct Cleaning Is Cotati’s Preferred Duct Sealing Company

We’ve been sealing ducts in Sonoma County since 2004, and Cotati sits at the center of our rotation. The Garrison Standard means our technicians arrive inside the quoted window, price the job in writing before touching a tool, and leave the site clean. No exceptions.

Cotati homeowners call us back because the price we quote is the price they pay. Our 365-Day Done Right Promise covers every duct sealing job in writing: if a sealed joint fails or a mastic application cracks within a year, we return and make it right at no charge, including a free second visit. That’s not a verbal assurance; it’s printed on your invoice.

Our technicians are background-checked and uniformed. You know who’s walking into your home before they arrive. And when you call (361) 326-5060, a live person answers, 24 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to ask why your bedroom vent blows lukewarm.

We also handle Air Duct Cleaning in Cotati and Dryer Vent Cleaning in Cotati, so one crew can address multiple system issues in a single visit.

Air Duct Sealing in Cotati

Air Duct Sealing in Cotati means finding and closing every gap, seam, and disconnected joint in your forced-air system so the air you paid to heat or cool actually reaches your rooms. In a town where morning coastal fog gives way to dry afternoon heat, that daily expansion and contraction cycle loosens mastic and separates flex-duct connections faster than inland climates. We seal with duct mastic, foil-backed tape rated for temperature cycling, and mechanical fasteners where the joint has pulled apart entirely.

Most Cotati homeowners need duct sealing when they notice uneven temperatures between rooms, dust pooling around return grilles, or utility bills that climb without explanation. A typical whole-home sealing job in Cotati runs $450 – $1,200 depending on system size, duct material, and accessibility. Single-room repairs or spot-sealing of visible disconnections start around $180 – $350.

What We Seal

We seal supply plenums, return boots, trunk line connections, and every flex-duct collar where the plastic meets the metal fitting. In Rancho Cotate’s tract homes, we often find the original builder’s tape has dried and fallen off where flex duct bends around framing. Downtown’s older metal systems usually need mastic reapplied at the furnace plenum and where trunk lines branch to individual rooms.

How We Test Our Work

After sealing, we pressurize the system and check for residual leakage with a smoke pencil or digital manometer. You’ll see the before-and-after difference in real numbers, not promises. If the pressure holds, we know your conditioned air is going where it belongs.

Duct Sealing Services in Cotati

Duct Sealing Services in Cotati cover everything from emergency repairs of disconnected trunk lines to full-system restoration of leaky flex duct. Our Duct Sealing team carries mastic rated for 200°F continuous exposure, foil tape with acrylic adhesive that won’t dry out in Cotati’s seasonal temperature swings, and replacement takeoff fittings for when the original connection has torn beyond repair.

The Sonoma coastal fog belt creates a unique problem here: cool, damp mornings followed by hot dry afternoons. That daily dew-and-dry cycle pushes fine particulate and pollen into every mastic joint and return grille, accelerating deterioration. We schedule Rancho Cotate’s builder-grade flex-duct systems on the hottest weekday mornings in August because the heat makes the duct plastic flexible enough to pull and seal without tearing. Downtown’s old metal octopus ducts get handled early, before afternoon fog makes the crawlspace too wet to work in. This is the kind of local scheduling knowledge you don’t get from a dispatcher in another state.

Metal Duct Restoration

Original galvanized steel ducts in the downtown cottages often have separated seams or rusted spots where decades of condensation collected. We clean the joint, apply fiberglass-reinforced mastic, and secure with sheet-metal screws where the metal has pulled apart. These systems can outlast the house if maintained.

Flex Duct Replacement and Sealing

When Rancho Cotate’s original flex duct has collapsed, torn at the collar, or been chewed by rodents in the crawlspace, we replace the damaged section with new insulated flex, seal with zip ties and mastic, and support with proper hangers so it doesn’t sag again. Sagging flex duct creates its own leaks, the weight pulling connections apart over time.

Trusted Brands We Service in Cotati

Our trucks stock sealing and filtration products from Honeywell, Aprilaire, and Abatement Technologies, plus the professional-grade tools to apply them correctly. We don’t run to the hardware store mid-job. For Cotati homeowners, that means faster turnaround and parts that match your existing system. If your return air pathway needs a Honeywell media cabinet sealed into the plenum, or an Aprilaire dehumidifier connected to the trunk line, we carry the fittings and the expertise to integrate it without callbacks. The same goes for Abatement Technologies HEPA filtration add-ons that require sealed duct transitions to maintain their rated efficiency. A filter is only as good as the ductwork around it.

Common Duct Sealing Problems We See in Cotati Homes

• Downtown cottage crawlspaces with original metal ducts pulling apart at the seams. The 1920s – 1960s stock around the hexagon used galvanized steel with locked seams, not welded, and eighty years of thermal cycling has opened gaps where conditioned air pours into the dirt below your floorboards.
• Rancho Cotate flex duct collapsed or disconnected at the collar. The cheap plastic duct national builders favored in the 1980s and 1990s hardens and cracks where it bends around framing members, or the zip ties simply snap after twenty years of vibration from the air handler.
• Return air pathways pulling attic dust through unsealed platform cavities. Many Cotati homes, especially the west-side subdivisions, have return air built into the floor platform with no actual duct, just the space between joists. If that cavity isn’t sealed at the edges, you’re filtering attic insulation and pollen through your system every time the blower cycles.
• Mastic joints failed from Cotati’s dew-and-dry climate cycle. The coastal fog belt’s daily moisture swing swells and shrinks old mastic until it cracks or falls off entirely, particularly on west-facing duct runs that catch afternoon sun after morning dampness.

Pricing for Duct Sealing in Cotati, CA

We Also Serve Cities Near Cotati

Our crews seal ducts across Sonoma County, including Cotati, Rohnert Park, Petaluma, Santa Rosa, and Sebastopol. The same written pricing, same 365-Day Done Right Promise, same background-checked technicians at every stop. If you’re on the edge of our service area and unsure, call (361) 326-5060 and we’ll confirm.

FAQs About Duct Sealing in Cotati