Duct Sealing in Los Altos Hills - Tested First, Written Price Second

Fast, Reliable Duct Sealing Across Los Altos Hills

Homes in Los Altos Hills lose an average of 20-30% of conditioned air through leaky ductwork, and in a town where custom estates on acre-plus lots often have duct runs stretching hundreds of feet through unconditioned crawlspaces, that waste adds up fast. We’re Hollis Air Duct Cleaning, and our crews handle Duct Sealing for Los Altos Hills properties from the mid-century ranchers near Purissima Road to the newer estates off Moody Road. Because our San Francisco Bay Area office coordinates dispatch locally, we arrive inside the quoted window and price the job in writing before touching anything. Call (361) 326-5060 for a free estimate.

Call (361) 326-5060

Why Hollis Air Duct Cleaning Is Los Altos Hills’s Preferred Duct Sealing Company

We’ve been sealing ducts in Los Altos Hills since 2004, and the work has taught us something no manual covers: how to navigate steep driveways with limited turnaround space while carrying equipment up to homes where the nearest neighbor might be a quarter-mile away. Our technicians are background-checked, uniformed, and trained to The Garrison Standard, which means they arrive squared away, explain what they found, and leave the site clean.

Los Altos Hills homeowners don’t shop for the lowest teaser price. They want the price that stays put. We write ours down before work starts, and it doesn’t move at the door. Our 365-Day Done Right Promise covers every sealing job in writing: if the mastic fails, a joint opens, or conditioned air starts escaping again 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 hours a day, 7 days a week. No voicemail loops, no callback queues, no waiting until Monday to schedule.

Air Duct Sealing in Los Altos Hills

Air Duct Sealing in Los Altos Hills means closing the gaps, seams, and disconnected joints in the metal or flex ductwork that carries heated and cooled air through homes where runs can span extraordinary distances. Because most properties here sit on 1-acre or larger lots under Hillside Residential zoning, ducts often travel through unheated crawlspaces, raised foundations, and attic spaces unique to each custom-built estate. We seal with mastic compound and metal-backed tape rated for thermal cycling, not the hardware-store duct tape that dries and peels within a season.

When Sealing Beats Replacement

Not every leaky system needs new ductwork. If your metal ducts are structurally sound but bleeding air at joints or connections, sealing restores efficiency for a fraction of the cost. In Los Altos Hills, where many homes have original mid-century ductwork still in good shape, this distinction saves homeowners thousands.

What the Process Looks Like

We pressurize the system, locate leaks with a smoke pencil or theatrical fog, then seal accessible points from the inside using a non-toxic, UL-181-rated mastic. For buried or vaulted runs, we access through existing panels or coordinate with your HVAC contractor if drywall work is needed.

Duct Sealing Services in Los Altos Hills

Duct Sealing Services in Los Altos Hills address the specific challenges of a town where no two floor plans are alike and ductwork is often routed through unconventional spaces like wine cellars or home theaters. The Mediterranean climate brings hot, dry summers and mild, wet winters, but the Santa Cruz Mountains microclimate means more fog and cooler nights than nearby Palo Alto. That temperature swing causes metal ducts to expand and contract, stressing joints and opening gaps over time. We also handle Air Duct Cleaning in Los Altos Hills and Dryer Vent Cleaning in Los Altos Hills for homeowners who want the full system addressed.

Whole-System Testing

Before we seal, we measure. Our crews run a duct blaster or pressure pan test to quantify leakage in CFM25, cubic feet per minute at 25 pascals of pressure. You get the number in writing, and we show you the improvement after sealing.

Post-Sealing Verification

Every job ends with a retest. If the leakage doesn’t drop to the target we agreed on, we keep working until it does. That’s part of the written price, not an upsell.

Trusted Brands We Service in Los Altos Hills

Our equipment roster includes Rotobrush rotary brush systems for pre-sealing cleaning, Nikro negative-air machines for containment, and filtration products from Aprilaire, Abatement Technologies, and Guardsman. We stock mastic, metal-backed tape, and mechanical fasteners sized for the oversized ductwork common in Los Altos Hills estates, so we’re not waiting on parts while your system stays open. For homeowners with Aprilaire whole-house dehumidifiers or Abatement Technologies HEPA filtration tied into their duct systems, we seal around those connections with the same care we bring to the main trunk lines.

Common Duct Sealing Problems We See in Los Altos Hills Homes

• Long runs through unconditioned crawlspaces. In Los Altos Hills, ducts often travel 100 feet or more beneath raised foundations where winter fog and cool nights create condensation. That moisture corrodes metal and degrades flex duct outer wraps, opening seams that leak conditioned air into the dirt.
• Vaulted ceiling supply registers with no attic access. Many custom homes here feature dramatic vaulted ceilings where ducts terminate at high wall registers. Without an attic above, leaks at the boot-to-drywall junction go unnoticed for years, dumping heated air into the wall cavity.
• Multi-zone systems with abandoned or bypassed dampers. Estates with multiple HVAC zones often have dampers that failed or were manually overridden. The resulting pressure imbalances force air out of every weak joint in the system, and sealing without addressing the damper just masks the symptom.
• Propane furnace connections stressed by thermal cycling. Because Los Altos Hills has no municipal gas utility, propane-fired furnaces cycle more aggressively than natural gas units. The expansion and contraction at plenum connections eventually cracks mastic and loosens flanges.

Pricing for Duct Sealing in Los Altos Hills, CA

We Also Serve Cities Near Los Altos Hills

Our San Francisco Bay Area office dispatches crews throughout the region, and we regularly handle Duct Sealing in Los Altos Hills alongside work in Los Angeles, San Diego, San Jose, and San Francisco. Each location operates independently under The Garrison Standard, so the same written pricing, background-checked technicians, and 365-Day Done Right Promise apply whether we’re sealing ducts on a hillside estate or a downtown flat.

FAQs About Duct Sealing in Los Altos Hills