Duct Sealing in Kensington - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Kensington

If you’re noticing uneven temperatures between rooms, rising energy bills, or dust that returns no matter how often you clean, your ductwork is likely leaking conditioned air into your attic, crawl space, or walls. In Kensington, where many homes were built during the post-WWII boom with galvanized steel ductwork now pushing 60 to 80 years old, those leaks are practically guaranteed. We’re Hollis Air Duct Cleaning, and our crews handle Duct Sealing throughout Kensington and the surrounding Bay Area. Dispatch and scheduling run from our San Francisco Bay Area office, but the technicians who arrive at your door know this town’s housing stock inside and out. Call us at (361) 326-5060 for a free estimate, and we’ll show you exactly where your system is bleeding efficiency before we quote a flat price to fix it.

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

We’ve been in business since 2004 as part of the Garrison Partners family, and that track record matters in a town like Kensington where word travels fast. Our technicians are background-checked and uniformed, and they operate under The Garrison Code: arrive inside the quoted window, price in writing before touching anything, complete the job by the book, and leave the site clean. Roy Castellanos, who leads Hollis Air Duct Cleaning, insists on this standard on every Kensington job.

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. When you call (361) 326-5060, you talk to a human who can book your appointment and confirm your written price.

Our Kensington customers receive the 365-Day Done Right Promise on every repair. If the work fails within a year, we return and make it right at no charge, including a free second visit. That guarantee is backed in writing, not mentioned verbally and forgotten.

Local knowledge separates a proper duct sealing job from a rushed one. Homes near the Town Center often have duct systems with poorly sealed joints from mid-century renovations, causing pressure imbalances that spike during peak heating and cooling seasons. Our crews recognize this pattern and address it directly rather than applying a one-size-fits-all fix.

Duct Sealing Services in Kensington

Duct Sealing Services in Kensington address the gaps, cracks, and failed joints in your forced-air system that waste energy and degrade indoor air quality. The process begins with a pressure test to locate leaks, followed by manual sealing with mastic compound or metal-backed tape rated for HVAC use, and sometimes aerosol-based duct sealing for inaccessible runs. Most Kensington homeowners need this service when rooms won’t hold temperature, utility bills climb without explanation, or allergy symptoms persist despite cleaning. A typical whole-home duct sealing in Kensington runs $1,200 – $2,800 depending on system size and accessibility, with smaller partial repairs starting around $650.

Pressure Testing and Leak Detection

We pressurize your duct system and measure airflow loss to pinpoint exactly where conditioned air escapes. In Kensington’s older homes with galvanized steel ductwork, we regularly find leaks at rusted seams in basement runs and at connections where mid-century renovations disturbed original joints. The test takes about 45 minutes and gives us a map of every problem area before we quote your flat price.

Mastic and Mechanical Sealing

Our technicians apply fiber-reinforced mastic, a thick compound that remains flexible after curing, to seal joints and small gaps. For larger separations or rusted sections, we use metal-backed tape and mechanical fasteners. This isn’t the hardware-store duct tape that dries and fails within a year. The materials we use are rated for continuous HVAC operation and backed by our 365-Day Done Right Promise.

Duct Insulation in Kensington

Duct Insulation in Kensington protects sealed ductwork from the temperature extremes in unconditioned spaces like attics and crawl spaces, where Bay Area temperature swings can reverse the gains of sealing alone. We install wrapped fiberglass insulation with vapor barriers or closed-cell foam sleeves, depending on your duct material and space constraints. Kensington homeowners typically need this when ducts run through unheated basements, when condensation forms on metal surfaces during humid periods, or when sealed ducts still can’t maintain target temperatures. Whole-system duct insulation in Kensington generally costs $800 – $1,900, with targeted sections running $300 – $700.

Vapor Barrier Installation

Kensington’s humid summers can drive moisture into uninsulated ductwork, promoting mold growth and degrading air quality. We install faced insulation with sealed vapor barriers that block this moisture transfer. This step is especially critical for homes with crawl space duct runs, where ground moisture meets cool metal surfaces.

Condensation Control

When cold air moves through warm, humid spaces, water condenses on duct exteriors and drips onto framing and insulation. Our insulation packages eliminate this surface temperature differential. We’ve found this problem particularly common in Kensington’s ranch-style homes with attic-mounted air handlers, where summer humidity concentrates in peak-roof cavities.

Trusted Brands We Service in Kensington

Our equipment roster includes professional-grade tools from Rotobrush, Nikro, and Abatement Technologies, plus filtration products from Honeywell, Aprilaire, and Guardsman. For Kensington customers, this means we stock common sealing mastics, mechanical fasteners, and insulation materials sized for the 6-inch and 8-inch galvanized ductwork found in most local homes. We don’t wait on special orders for standard jobs. When your system needs a specific fitting or insulation R-value, our technician typically has it on the van. That translates to faster completion and fewer return visits, which matters when you’re already dealing with uneven temperatures and rising utility bills.

Common Duct Sealing Problems We See in Kensington Homes

• Failed seams in original galvanized steel. Kensington’s housing stock is dominated by homes built between 1940 and 1980, and the galvanized ductwork in these properties has had decades to rust internally. We regularly find pinhole leaks and separated seams in basement trunk lines where condensation has collected for years.
• Disrupted joints from mid-century renovations. Homes near the Town Center often show evidence of hasty 1960s and 1970s remodeling, where walls were moved and ducts were extended with poorly fitted connections. These joints leak continuously and create pressure imbalances that strain your HVAC equipment.
• Leaf litter and pollen infiltration through gaps. Kensington’s heavy oak and maple canopy sheds debris that standard cleaning can’t fully address. When ducts leak in wall cavities or crawl spaces, that organic material gets pulled into the system and distributed through your home.
• Humidity-driven mold in uninsulated runs. The combination of humid summers and cold winter air creates ideal conditions for mold growth in uninsulated ductwork. Sealing alone won’t solve this; proper insulation with vapor barriers is required to break the moisture cycle.

Pricing for Duct Sealing in Kensington, CA

We Also Serve Cities Near Kensington

Our crews travel throughout the region for homeowners who need reliable duct sealing beyond Kensington city limits. We regularly serve Los Angeles, San Diego, San Jose, and San Francisco with the same written pricing, uniformed technicians, and 365-Day Done Right Promise that Kensington customers receive. Scheduling is coordinated from our San Francisco Bay Area office to keep response times predictable across all service areas.

FAQs About Duct Sealing in Kensington