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.
Fast, Reliable Duct Sealing Across Menlo Park
We’re the crew Hollis Air Duct Cleaning dispatches from our San Francisco Bay Area office when Menlo Park homeowners call about musty duct smells, rooms that never cool evenly, or energy bills that climbed without explanation. Most of our Duct Sealing in Menlo Park calls come from the Willows, Allied Arts, or Sharon Heights, and we typically schedule within a few business days. You can reach us at (361) 326-5060. We know the local housing stock: the pre-1920s bungalows with original gravity-furnace ducting, the Eichler-era slab-duct ranches, and the newer zoned systems near Stanford. That familiarity means we diagnose faster and quote accurately before we touch anything.
Why Hollis Air Duct Cleaning Is Menlo Park’s Preferred Duct Sealing Company
We’ve been part of the Garrison Partners family since 2004, and our Duct Sealing team has built a reputation in Menlo Park on one thing: doing what we said we’d do. Our technicians are background-checked, uniformed, and expected to follow The Garrison Code on every job. That means arriving inside the quoted window, pricing in writing before any work starts, and leaving the site clean.
Menlo Park homeowners looking for Menlo Park Dryer Vent Cleaning aren’t looking for the lowest teaser quote. They’ve seen the coupon offers that balloon once the van is in the driveway. Hollis does the opposite: one flat price per system, agreed on paper, with a 365-Day Done Right Promise. If the work fails within a year, we come back at no charge, including a free second visit. Our phones are answered by a live person 24 hours a day, 7 days a week. No voicemail loops. No waiting until Monday for a callback.
We serve Menlo Park neighborhoods from the Willows to Belle Haven to the streets near Sand Hill Road, and our crews carry the equipment to handle both century-old unlined returns and modern high-SEER zoned systems.
HVAC Duct Sealing in Menlo Park
HVAC Duct Sealing in Menlo Park is often the real fix behind complaints that start out sounding like cleaning jobs. A homeowner notices one bedroom stays warm, or the utility bill jumps 20 percent, or there’s a faint mustiness when the system cycles. The cause is usually air leaking from supply ducts into the attic or crawlspace, or return ducts pulling in unconditioned air from outside the building envelope. In Menlo Park specifically, we see a second driver: the marine layer. Cool, damp air sits in unlined crawlspace and attic ducts in the Willows and Allied Arts, so we routinely find condensation-wet flexible foil runs and microbial growth that a dry-climate city like Livermore or San Jose would never see at the same age. Sealing the duct system closes those pathways, restores designed airflow, and stops the moisture intrusion that feeds the problem.
A typical HVAC duct sealing job in Menlo Park runs $1,200 – $2,800 for a whole-house system, depending on accessibility, duct material, and whether we’re working with original gravity-furnace metal or newer flex runs. We inspect first, photograph what we find, and give you a written price before any sealing begins.
Supply Duct Sealing
Supply ducts push conditioned air to your rooms. When they leak into a 130°F Menlo Park attic, you’re paying to cool space you don’t use. We seal joints, connections, and register boots with mastic rated for the temperature range, then pressure-test to verify the improvement.
Return Duct Sealing
Return leaks are worse. They pull in crawlspace air, garage fumes, or attic dust and send it straight to your blower. In pre-1920s Menlo Park homes with unlined returns, this is where we find the condensation and microbial growth. Sealing returns often improves indoor air quality more than any filter upgrade.
Duct Repair in Menlo Park
Duct Repair in Menlo Park covers the physical damage we find once we’re inside the system: collapsed flexible foil in low-pitch attics, disconnected trunk lines, rusted metal at condensate points, and rodent damage in crawlspaces. The 1950s-60s Eichler and tract homes in Sharon Heights and Belle Haven are especially prone to slab-duct issues and undersized runs that were never designed for modern airflow. A homeowner in the Allied Arts neighborhood near downtown called us about a musty smell and uneven cooling in their 1920s bungalow. Our tech ran a camera inspection through the original unlined gravity-furnace return and found collapsed flexible foil duct in the low-pitch attic, plus condensation-wet insulation where the marine air had been sitting. We sealed the supply and return ducts at the air handler and registers, re-supported the flex run, and the static pressure and smell both improved on the first test.
Duct repair in Menlo Park typically costs $400 – $1,500 for localized fixes, or $1,800 – $3,500 if we’re replacing multiple flex runs or repairing slab-duct access points. We always scope the work with a camera first so you see what we see.
Collapsed Flex Duct Replacement
Menlo Park’s low-pitch roofs trap summer attic heat above 130°F, which degrades flexible foil duct faster than in steeper pitches with better ventilation. We replace collapsed runs with properly supported, insulated flex or rigid metal where the static pressure demands it.
Slab Duct Diagnosis
Eichler homes in Sharon Heights often have in-slab ducting that’s impossible to seal conventionally. We use camera inspection and pressure testing to determine whether the slab run can be sealed from inside or needs rerouting above grade. We tell you honestly which path makes sense.
Trusted Brands We Service in Menlo Park
Our vans carry professional-grade equipment from Rotobrush, Nikro, and Abatement Technologies, plus filtration products from Honeywell, Aprilaire, and Guardsman. We don’t use hardware-store gear. For Menlo Park homeowners, that means we can source the right mastic, tape, and register boots for your specific system without waiting on a parts run to San Jose. Our rotary brush systems handle the original metal ducting common in Willows bungalows, while our negative-air machines and HEPA filtration protect the high-SEER zoned systems near Stanford during any cleaning that precedes sealing. We stock fittings for Honeywell and Aprilaire media cabinets, and Guardsman UV accessories where microbial control is part of the scope.
Common Duct Sealing Problems We See in Menlo Park Homes
- Condensation-wet returns in Willows crawlspaces. The marine layer keeps humidity high year-round. Unlined gravity-furnace returns in pre-1920s homes pull that damp air straight into the system. Sealing only the visible registers while leaving these returns open is cosmetic; the moisture keeps feeding microbial growth.
- Collapsed flex duct in low-pitch attics. Summer attic temperatures in Menlo Park exceed 130°F, softening flexible foil until it crushes under its own weight or the weight of dust accumulation. Mastic over the crush doesn’t restore airflow; the duct needs re-support or replacement.
- Slab-duct failures in Sharon Heights Eichlers. In-slab ducts weren’t designed for modern static pressure or filtration. One room that never cools usually means a slab leak or blockage, not a dirty register. We camera-inspect to confirm before quoting.
- Fogging “sanitiser” upsells that mask the real problem. A chemical fog might kill surface mold temporarily, but it does nothing about damp debris, collapsed duct, or the MERV rating gap that let contamination accumulate in the first place. Source removal under negative pressure and HEPA filtration, followed by proper sealing, is the only durable fix.
Pricing for Duct Sealing in Menlo Park, CA
Duct sealing in Menlo Park runs $1,200 – $2,800 for most whole-house systems. Duct repair ranges from $400 for a single collapsed flex run to $1,500 for multiple connection fixes, with slab-duct or full replacement work reaching $1,800 – $3,500. What moves the number: attic accessibility (low-pitch Menlo Park attics are tight), whether we’re sealing original metal or replacing degraded flex, and whether the job requires camera inspection or pressure testing to diagnose hidden issues.
We do not quote per-vent. We price per system, in writing, before work starts. The price does not move at the door. Every Menlo Park job includes before-and-after photos of your own ducts, not stock images. Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Menlo Park
Our crews work throughout the mid-Peninsula. We regularly dispatch to Menlo Park, Atherton, Stanford, Palo Alto, and Redwood City from our San Francisco Bay Area office. Same standards, same written pricing, same 365-Day Done Right Promise in every city we serve.
Serving Menlo Park, CA - Our Local Coverage Area
We’re based in the Menlo Park 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 Menlo Park
The marine layer sits on Menlo Park longer and heavier than on the drier east side of the Peninsula or farther north. Cool, damp air lingers in unlined crawlspace and attic ducts in the Willows and Allied Arts, creating condensation that dry-climate cities don’t see at the same duct age. Sealing the returns and supply paths stops that moisture intrusion. Call (361) 326-5060 for an inspection and exact quote.
It’s usually a duct repair or sealing problem, not a cleaning issue. Slab ducts in Eichlers were undersized for modern airflow and often crack or block over decades. We camera-inspect to determine if the slab run can be internally sealed or needs rerouting above grade. Cleaning a blocked slab duct doesn’t restore airflow. Call (361) 326-5060 and we’ll scope it.
No. Fogging kills surface mold temporarily but leaves damp debris, collapsed duct, and the unsealed moisture pathway untouched. The smell returns within weeks. We remove contamination with source removal under negative pressure and HEPA filtration, then seal the ducts to stop the marine-layer moisture that feeds regrowth. Call (361) 326-5060 for the durable fix.
We can seal accessible metal duct and register connections, but we do not disturb friable asbestos wrap. If your pre-1920s Willows or Allied Arts home has asbestos-wrapped ducts, we’ll note it during inspection and recommend a certified asbestos abatement contractor for any wrap removal before we proceed with sealing. We document what we find and adjust the scope accordingly. Call (361) 326-5060 to discuss your specific situation.
We pressure-test before and after, show you the numbers, and provide photos of the sealed joints. You should feel more even airflow room-to-room, and your system should cycle less frequently. If the musty smell or uneven cooling persists, our 365-Day Done Right Promise covers a free return visit to make it right. Call (361) 326-5060 if you have concerns after the job.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Menlo Park and the Bay Area since 2004.




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