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 Piedmont
Most Piedmont homes were never built for ducted air. If you’re dealing with uneven heating, musty attic air, or a retrofitted system stuffed into original joist bays, you’re not alone. Our Duct Sealing crew serves Piedmont from our San Francisco Bay Area dispatch office, and we know the specific headaches these historic properties create. We arrive inside the quoted window, price the work in writing before touching anything, and back it with our 365-Day Done Right Promise. Call (361) 326-5060 for a free estimate.
Why Hollis Air Duct Cleaning Is Piedmont’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 online. Piedmont homeowners looking for Piedmont Dryer Vent Cleaning aren’t after the cheapest coupon. They’re looking for a crew that shows up uniformed, background-checked, and prepared for what these old houses actually contain.
Our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No callback queues. When you schedule Duct Sealing in Piedmont, you get a written price before any work starts, and that number does not move at the door. If the repair fails within a year, we return and make it right at no charge, including a free second visit. That’s the 365-Day Done Right Promise, backed in writing on every job.
We run by The Garrison Standard: arrive inside the window, price in writing, complete the job by the book, leave the site clean. No exceptions.
Duct Repair in Piedmont
Duct Repair in Piedmont often means something different than in a newer suburb. Here, we’re frequently working on retrofitted forced-air systems that were shoehorned into homes built for gravity furnaces, with ducts squeezed through shallow fir joist bays or uninsulated attics where original lath-and-plaster walls can’t be disturbed.
A typical duct repair in Piedmont runs $280 – $620 depending on accessibility, the extent of damaged sections, and whether we need to navigate around legacy building materials. We inspect with a camera first, then explain what we found before quoting.
When Repair Becomes Replacement
Some Piedmont crawl spaces still contain abandoned asbestos-wrapped ducts or transite pipes from the original octopus furnace. We don’t disturb that material. If our camera inspection reveals damaged legacy ductwork, we’ll flag it for proper abatement and quote repair only on the active, accessible lines.
Moisture-Damaged Joints
The marine layer and hill fog that roll through Piedmont’s East Bay hills introduce damp air into attic ducts, especially where insulation is thin or missing. We see rusted metal joints and separated flex duct at attic takeoffs. We cut out the damaged section, seal with mastic, and recommend insulation upgrades only where they’ll actually help.
Air Duct Sealing in Piedmont
Air Duct Sealing in Piedmont is often a partial installation or sealing job rather than a simple seal-up of an existing modern system. Because most properties here were built before 1940 with no ductwork, retrofitted systems run through tight, original framing cavities that require careful routing without altering visible historic features.
A typical air duct sealing project in Piedmont runs $420 – $890 for partial sealing in accessible areas, or $1,200 – $2,400 when we’re installing and sealing new duct runs through original joist bays in a home that never had a modern forced-air system. We quote by the system, not by the vent.
Mastic Sealing vs. Tape
We seal joints and boots with Guardsman mastic, a brush-applied compound that remains flexible and won’t degrade like foil tape in damp attic conditions. In Piedmont’s minimally insulated attics, tape fails within a few seasons. Mastic doesn’t.
Sealing Without Disturbing Historic Fabric
Piedmont has its own building department and strict design-review rules. Our technicians are trained to route ductwork through existing cavities, not cut new chases through visible plaster or exterior features. We plan the seal path before we touch a tool.
Trusted Brands We Service in Piedmont
We stock parts and filtration products from Honeywell, Aprilaire, and Abatement Technologies for Piedmont customers, which means faster turnaround when your system needs a component swap during sealing work. Our equipment roster also includes Nikro negative-air machines and Rotobrush rotary brush systems, the same tools commercial crews use. We don’t show up with hardware-store gear. When we find a Honeywell media filter housing that’s rusted out from hill-fog moisture, or an Aprilaire humidifier that’s been feeding microbial growth, we can replace it same visit because we carry the parts.
Common Duct Sealing Problems We See in Piedmont Homes
- Gravity-furnace legacy in Craftsman and Tudor homes. Many Piedmont properties still have abandoned asbestos-wrapped ducts or transite pipes in crawl spaces from the original octopus furnace. Sealing over these without proper abatement handling disturbs hazardous material and violates basic safety protocol.
- Hill-fog moisture in attic duct runs. The marine layer penetrates minimally insulated attics, especially in homes near the higher elevations around Wildwood Gardens. Damp air condenses on metal ducts, rusts joints, and feeds mold at takeoffs. Sealing the joints without first addressing the moisture traps the problem inside.
- Shallow joist bays with no room for proper insulation. Retrofitted ducts in original fir framing often sit directly against wood with no air gap. In winter, warm supply air hits cold joist surfaces and sweats. In summer, cool return air draws in attic heat. Sealing helps, but only if the routing allows it.
- Oak and eucalyptus pollen loading the system. Piedmont’s mature tree canopy is protected by strict local ordinances, which is good for the neighborhood character and hard on ductwork. Pollen and leaf debris enter through gaps in attic returns and clogged exterior vents, coating the ducts that were never designed to handle it.
Pricing for Duct Sealing in Piedmont, CA
We’re upfront about what this costs because we’ve seen what bait-and-switch pricing does to homeowners in this market.
| Service | Typical Range in Piedmont |
|---|---|
| Basic duct sealing (accessible joints, single system) | $420 – $890 |
| Partial duct sealing with repair in joist bays | $680 – $1,450 |
| New duct installation and sealing (no existing ductwork) | $1,200 – $2,400 |
| Camera inspection and assessment | $95 – $150 (credited toward work) |
What moves the price: accessibility (crawl space vs. full attic), whether we need to work around legacy asbestos material, the linear feet of duct involved, and whether the job requires new takeoffs or boot connections. We do not quote per-vent. One flat price per system, agreed in writing before work starts. Estimates are free. Call (361) 326-5060.
We Also Serve Cities Near Piedmont
Our crews work throughout the East Bay, including Duct Sealing calls in Emeryville, Oakland, Alameda, and Berkeley. Each city has its own housing stock quirks, but the same Garrison Standard applies: written price, written guarantee, job done by the book.
Serving Piedmont, CA - Our Local Coverage Area
We’re based in the Piedmont 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 Piedmont
Duct sealing is likely a partial misnomer for what you actually need. Most pre-1940 Piedmont homes were built for gravity furnaces with no ductwork, so what you’re probably after is a combination of new duct installation and sealing in original framing cavities. We assess with a camera first, then quote exactly what’s required. Call (361) 326-5060 for a free estimate.
The marine layer and hill fog bring damp air year-round, especially into minimally insulated attics where retrofitted ducts sit against cold joist bays. Even in dry August, morning fog condenses on metal surfaces. Sealing the joints without first removing the moisture source traps that dampness inside the duct runs. We use negative-pressure source removal to NADCA standards, then seal with mastic, not a fogging fragrance mask.
We stop work and flag it immediately. Many Piedmont crawl spaces still contain abandoned asbestos-wrapped ducts or transite pipes from original octopus furnaces. We do not disturb this material. We’ll document the location, recommend a licensed abatement contractor, and resume sealing work only on the active, accessible duct lines once the hazard is properly handled.
Yes. Piedmont’s strict tree-protection and design-review ordinances mean exterior penetrations, new vents, or visible modifications often require planning department coordination. We route ductwork through existing interior cavities whenever possible to avoid triggering review. If exterior work is unavoidable, we’ll flag it in our written quote so you know before we start.
No. A fragrance mist does nothing about the oak and eucalyptus pollen, hill-fog moisture, and attic mold that actually load Piedmont’s ductwork. Genuine source removal with negative-air machines and HEPA filtration, followed by proper mastic sealing, addresses the real problem. We don’t upsell fogging. Call (361) 326-5060 and we’ll explain what your specific system actually needs.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Piedmont and the East Bay since 2004.