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 Sonoma
Duct sealing in Sonoma typically runs $450 – $1,200 for a whole-home system, and most jobs are completed in a single visit after a written estimate. We’re the Duct Sealing in Sonoma crew that shows up when we said we would, prices it before we touch it, and leaves the site clean. Our dispatch and scheduling are coordinated from our San Francisco Bay Area office, but our technicians live and work in Sonoma County, so we know the difference between a Plaza-area Victorian with retrofitted ductwork and a mid-century ranch off Napa Road. Call (361) 326-5060 for a free estimate. We’ll answer live, 24 hours a day.
Why Hollis Air Duct Cleaning Is Sonoma’s Preferred Duct Sealing Company
We’ve been part of the Garrison Partners family since 2004, and our Sonoma customers know what that means: written prices, written guarantees, and technicians who arrive uniformed and background-checked. Our 365-Day Done Right Promise covers every duct sealing job in writing. 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, 24/7. No voicemail loops. No callback queues. When you call (361) 326-5060, you talk to a human who can book your appointment and confirm your written estimate window.
We serve homes from the historic Plaza district out to the newer developments along East Napa Street and the vineyards beyond Boyes Hot Springs. That local knowledge matters. A technician who doesn’t know Sonoma’s housing stock might recommend a full replacement when what you actually need is reconnection and sealing at the plenum.
HVAC Duct Sealing in Sonoma
HVAC Duct Sealing in Sonoma is often the real fix for homes where conditioned air never reaches the rooms it’s supposed to serve. The job involves locating leaks in your duct system, disconnections at the trunk or plenum, and gaps where retrofitted runs pass through unsealed wall or crawlspace cavities. We use duct sealing mastic, fiberglass mesh reinforcement, and metal-backed tape at all seams and joints, then verify the repair with a static pressure test at the air handler. In Sonoma’s market, a typical whole-home HVAC duct sealing job runs $450 – $1,200 depending on system size, accessibility, and whether we find disconnected runs that need reconnection before sealing can begin.
Most of our Sonoma calls come from homeowners who’ve already had their ducts cleaned once or twice but still have hot rooms, cold rooms, or dust that returns within weeks. If you’re dealing with persistent dust after cleaning, our Sonoma Dryer Vent Cleaning service may also be worth considering as part of a complete solution. Cleaning removes debris. Sealing stops the leaks that let new debris in and conditioned air out.
Sealing Retrofitted Systems in Historic Homes
In Sonoma’s historic Plaza-area homes, the original redwood or fir framing was rarely built with duct chases, so retrofitted duct runs are often snaked through unsealed attic and crawlspace cavities and left disconnected at the trunk. The sealing fix is usually reconnecting and sealing runs at the plenum, not adding sealant to a system that was never properly connected. We’ve found runs dumping conditioned air straight into crawlspaces for years while the homeowner pays to heat and cool dirt.
Pre-Sealing Cleaning Requirements
Sealant won’t bond to a fouled duct surface. In Sonoma, that means cleaning must come first, especially during and after harvest season when grape must and wildfire ash coat the interior. Our Duct Sealing team uses HEPA-filtered negative-air machines from Nikro and rotary brush systems from Rotobrush to prep the surface before any mastic goes on.
Duct Repair in Sonoma
Duct Repair in Sonoma addresses the physical damage we find in duct systems: crushed flexible runs, disconnected branches, corroded metal trunk lines, and pest damage in crawlspaces. The repair may involve replacing a section of duct, reconnecting a branch to the trunk, or rebuilding a damaged plenum. Costs in Sonoma typically run $200 – $600 for isolated repairs and $800 – $1,500 when multiple runs or the main trunk need attention. We always inspect with a camera first, show you what we found, and give you a written price before any work starts.
On a 1908 Victorian near the Plaza, our tech ran a camera inspection and found a crushed 6-inch branch run that had pulled loose from the trunk and was dumping conditioned air straight into the crawlspace. The homeowner thought she needed a whole-system replacement. We reconnected and sealed the run with mastic and mesh, sealed the plenum seams, and verified static pressure at the air handler before we left. Her August cooling bill dropped noticeably and the musty smell in the hallway register was gone.
Crushed and Disconnected Runs
Flexible ducting in newer east-side Sonoma homes can sag, crush, or pull loose at the collar. Older metal systems in Plaza-area homes corrode at the seams. Both problems waste energy and circulate crawlspace or attic air into your living space. We replace damaged sections with new flex or metal as appropriate, never just tape over a failing joint.
Moisture-Damaged Ductwork
Sonoma’s occasional damp winters can cause moisture intrusion in poorly insulated duct runs, especially flexible ducting in newer homes. Sealing over damp flex traps mold instead of stopping the leak. The duct has to be dried and assessed before any sealing. We use moisture meters and camera inspection to confirm the system is dry and sound.
Trusted Brands We Service in Sonoma
We stock parts and filtration products from Honeywell, Aprilaire, and Abatement Technologies for fast turnaround on Sonoma jobs. Our equipment roster includes Nikro negative-air machines and Rotobrush rotary brush systems, the same tools commercial crews use. When we seal your ducts, we use professional-grade mastic and mesh, not hardware-store tape that will fail in six months. If your system includes Honeywell or Aprilaire filtration components, we can assess their condition during the sealing visit and replace them if needed, so you don’t wait on a second appointment.
Common Duct Sealing Problems We See in Sonoma Homes
- Disconnected retrofitted runs in Plaza-area Victorians. Original redwood framing lacked duct chases, so decades-old retrofits pull apart at the trunk and leak into crawlspaces. Sealing alone won’t fix a disconnected run. We reconnect first, then seal.
- Harvest-season grape must coating duct interiors. From August through October, vineyards surrounding Sonoma release a fine, sticky film that traps wildfire ash on register grilles and return inlets. Sealant won’t adhere to this layer. Cleaning is mandatory first.
- Winter moisture in east-side flexible ducting. Newer homes with flex runs can hold moisture after rare heavy rains, creating mold-friendly conditions. Sealing over this traps the problem. We dry, assess, and replace damaged flex before sealing.
- Fire-season ash infiltration from the Mayacamas and Sonoma Mountains. Recurring wildfires fill Sonoma’s air with fine particulates that enter duct systems through leaks and accumulate in trunk lines. Sealing stops the inflow, but existing ash must be removed or it will continue circulating.
Pricing for Duct Sealing in Sonoma, CA
A typical whole-home duct sealing in Sonoma runs $450 – $1,200. Isolated duct repair runs $200 – $600. Larger repairs involving multiple runs or trunk replacement range $800 – $1,500. What moves the price: system size, attic or crawlspace accessibility, whether we find disconnected runs that need reconnection before sealing, and whether pre-sealing cleaning is required due to grape must, ash buildup, or mold.
We give one flat price per system, agreed in writing before work starts. No per-vent pricing. No add-ons at the door. Estimates are free. Call (361) 326-5060.
We Also Serve Cities Near Sonoma
Our crews work throughout Sonoma County and beyond, including Sonoma, Boyes Hot Springs, Petaluma, Novato, and Cotati. Same written pricing, same 365-Day Done Right Promise, same live-answer phones at (361) 326-5060.
Serving Sonoma, CA - Our Local Coverage Area
We’re based in the Sonoma 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 Sonoma
Cleaning removes debris. Sealing stops the leaks that let new debris in and conditioned air out. In Sonoma’s historic homes with retrofitted ductwork, we’ve often found that disconnected runs at the plenum are the real problem, not dirty ducts. A third cleaning won’t reconnect a branch that’s dumping air into your crawlspace. Call (361) 326-5060 and we’ll camera-inspect to tell you which you actually need.
Yes. From August through October, grape must and vineyard dust create a sticky film on duct surfaces that sealant cannot bond to. We clean first with HEPA-filtered negative-air equipment, then seal. Skipping the cleaning step means the sealant fails. We include this assessment in every free estimate.
Often it’s the best investment you can make. Plaza-area homes from the late 1800s to early 1900s were retrofitted with ductwork that was rarely properly connected at the trunk. Sealing and reconnecting these runs restores airflow and cuts energy waste without the cost of full replacement. We’ve done this work on dozens of Sonoma Victorians with measurable results.
Flexible ducting in newer homes can sag, crush, or pull loose at collars, and it holds moisture more readily than metal. Sealing the joints and supporting the runs properly prevents mold growth and maintains airflow. But we always inspect for moisture damage first. Sealing over damp flex makes the problem worse.
Recurring fires fill Sonoma’s air with fine ash that infiltrates duct systems through leaks and accumulates in trunk lines. Sealing stops the inflow. But existing ash must be removed first or it will continue circulating through your home. We use Nikro negative-air machines and HEPA filtration to clean before we seal, and we verify the seal with static pressure testing.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Sonoma since 2004.