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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Before
AfterFast, Reliable Duct Sealing Across Burlingame
Most Burlingame homeowners with musty supply registers or rooms that never reach temperature are losing 20 – 30% of their conditioned air through leaky duct seams. Duct sealing in Burlingame typically runs $850 – $2,400 for a whole-home seal, depending on whether we’re working with original galvanized trunk lines in a 1930s bungalow or modern flex duct in a Bayfront townhome. Call (361) 326-5060 and we’ll send a technician with a written price before any work starts.
We know Burlingame’s housing stock because we’ve worked it for years. From the pre-war bungalows in Burlingame Park and Easton Addition to the newer construction along the Bayfront near Old Bayshore Highway, our crews have sealed ducts in crawlspaces that pull damp bay air, attics that bake in summer sun, and utility closets in downtown condos. Dispatch is coordinated from our San Francisco Bay Area office, and we keep our scheduling tight so you’re not waiting half a day for a technician who shows up in a personal vehicle with a roll of foil tape.
Why Hollis Air Duct Cleaning Is Burlingame’s Preferred Duct Sealing Company
Hollis Air Duct Cleaning has been part of the Garrison Partners family since 2004, and our Duct Sealing in Burlingame crews operate under The Garrison Standard: written price before work starts, background-checked uniformed technicians, and a 365-Day Done Right Promise backed in writing on every job. If our seal fails within a year, we come back and make it right at no charge, including a free second visit.
Our Burlingame customers aren’t looking for the cheapest bid. They’re looking for the bid they can trust. That’s why we explain exactly what we’re sealing, show camera footage of the leaks we found, and leave you with before-and-after photos of your own ductwork. No fogging upsells. No per-vent pricing games. One flat price per system, agreed before we touch anything.
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.
HVAC Duct Sealing in Burlingame
HVAC Duct Sealing in Burlingame means closing the gaps, seams, and disconnected joints in your forced-air distribution system so the air you paid to heat or cool actually reaches the rooms it was meant for. In Burlingame’s climate, this work matters more than it does inland. The cool, moist marine air that rolls off the Bay seeps into crawlspaces and attics, and when your return ducts are pulling from those spaces through unsealed seams, you’re circulating humidity and whatever spores it carries into every room of the house.
A typical whole-home HVAC duct sealing job in Burlingame runs $850 – $2,400. Smaller partial seals or single-branch repairs can run $350 – $750. The price depends on duct material, accessibility, and whether we’re working around asbestos wrap that needs assessment first.
When Sealing Beats Replacement
Not every leaky duct needs to be torn out. Galvanized steel trunk lines in Burlingame Park and Easton Addition homes often just need proper mastic and mesh at the seams and branch takeoffs. The metal itself can last decades. We seal what can be sealed and flag what actually needs replacing, so you’re not paying for ductwork you don’t need.
What Proper Sealing Includes
Our Duct Sealing technicians pressurize the system to locate leaks, then seal accessible seams with mastic and fiberglass mesh, not foil tape that peels in damp crawlspaces. We re-insulate where wrap has degraded, balance dampers for even airflow, and test static pressure before and after so you see the improvement in hard numbers.
Duct Repair in Burlingame
Duct Repair in Burlingame addresses the physical damage that sealing alone won’t fix: corroded galvanized steel, collapsed flex duct, disconnected branch lines, and degraded insulation that’s letting conditioned air escape into your crawlspace or attic. In Burlingame’s coastal environment, these problems develop faster than they do inland because salt air accelerates metal corrosion and humidity softens flex duct supports until they sag or kink.
Duct repair in Burlingame typically costs $450 – $1,800 depending on the extent of damage and whether we need to navigate tight crawlspaces or remove degraded asbestos wrap for safe access. We always provide a written price before starting, and we photograph the damage so you understand what we’re fixing and why.
Corroded Galvanized and Asbestos Wrap
In Easton Addition and Burlingame Park, we regularly find original galvanized ducts with pinhole corrosion at the seams, wrapped in asbestos-containing material that has cracked or settled. We can’t just seal over this. The wrap has to be assessed and stabilized first, or the seal fails in one wet season and damp bay air keeps pulling through. Our technicians are trained to recognize these conditions and handle them safely.
Flex Duct Kinks and Collapses
Newer Bayfront townhomes and downtown condos often use flexible ducting that’s prone to kinking at tight bends or collapsing where supports have failed. Sealing kinked flex duct raises static pressure and strains your blower motor without fixing airflow. We replace damaged sections with properly supported flex or rigid duct where appropriate, then seal the connections.
Trusted Brands We Service in Burlingame
We stock parts and filtration products from Honeywell, Aprilaire, and Abatement Technologies for Burlingame customers, which means faster turnaround when your system needs a component replaced during a seal or repair. Our equipment roster includes Nikro negative-air machines and Rotobrush rotary systems for the cleaning work that often precedes sealing, plus professional-grade mastic, mesh, and insulation materials that hold up in Burlingame’s humid crawlspaces. We don’t use hardware-store tape or consumer-grade sealants that peel or crack within a year.
Common Duct Sealing Problems We See in Burlingame Homes
- Asbestos-wrapped galvanized ducts in unheated crawlspaces. Many Burlingame Park and Easton Addition bungalows have original duct runs sitting below floor level where damp bay air circulates freely. The asbestos wrap degrades, the metal corrodes at seams, and the return pulls musty air straight into the living space. Sealing without assessing the wrap first is a temporary fix at best.
- Flex duct kinking in newer Bayfront construction. Tight framing and multiple bends in townhome utility chokes lead to collapsed or restricted flex runs. Homeowners call us for “poor airflow” when the real problem is a duct that’s been pinched since installation. Sealing a kinked duct makes the blower work harder, not smarter.
- Disconnected branch takeoffs in attic systems. Burlingame’s temperature swings between cool foggy mornings and warm afternoons cause duct expansion and contraction. Over years, branch connections loosen in attics, dumping conditioned air into insulation. We find these with pressure testing, not guesswork.
- Microbial growth from humidity, not dirt. The marine climate means ducts don’t need to be filthy to grow mold. They just need sustained humidity above 60%. A fogging “sanitiser” masks the odor but doesn’t remove the biofilm or fix the moisture source. Source removal plus proper sealing does.
Pricing for Duct Sealing in Burlingame, CA
Duct sealing in Burlingame runs $850 – $2,400 for most whole-home systems. Partial seals or single-problem repairs fall in the $350 – $750 range. What moves the price: duct material (galvanized steel takes more labor than flex), accessibility (crawlspace work costs more than attic access), whether asbestos wrap needs assessment and stabilization, and the extent of corrosion or physical damage we find.
We don’t quote per-vent prices. That’s a teaser tactic that balloons once the technician is inside. We inspect your system, show you what we found, and give one flat price for the complete seal before any work begins. Written down. No movement at the door.
Estimates are free. Call (361) 326-5060 to schedule.
We Also Serve Cities Near Burlingame
Our crews work throughout the Peninsula, including San Mateo, Millbrae, San Bruno, and Belmont. Each job gets the same written price, same uniformed technicians, and same 365-Day Done Right Promise we offer in Burlingame.
Serving Burlingame, CA - Our Local Coverage Area
We’re based in the Burlingame 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 Burlingame
Yes, the marine climate genuinely raises mold risk in Burlingame ductwork. Cool, moist bay air keeps crawlspace humidity high for months, and when return ducts pull from those spaces through unsealed seams, the moisture condenses on duct walls where dust provides a food source. We’ve camera-inspected enough Burlingame systems to know it’s not theoretical. Call (361) 326-5060 for a free inspection and we’ll show you what your ducts actually look like inside.
We can, but the wrap has to be assessed first. Sealing over degraded asbestos wrap without stabilizing it means the seal fails when the wrap shifts or crumbles, and damp crawlspace air keeps entering. Our technicians identify asbestos-containing materials, secure or replace wrap as needed, then seal the metal seams with mastic and mesh. The 365-Day Done Right Promise covers our work for a full year.
Burlingame bungalows often have duct runs through unheated crawlspaces open to the outside, pulling damp bay air directly into the return. Newer townhomes have conditioned or sealed mechanical spaces. The bungalow’s design multiplies the energy penalty and microbial risk of every leak. In a townhome, a small leak might waste air; in an Easton Addition crawlspace, it circulates musty, humid air through the entire house.
No. Fogging agents mask odors temporarily but don’t remove biofilm or fix the moisture source that allows microbial growth. In Burlingame’s humid crawlspace conditions, the smell returns within weeks. We recommend source removal with professional-grade equipment if contamination is present, followed by proper sealing to keep humid air out. That’s what actually solves the problem. Call (361) 326-5060 and we’ll explain what your specific system needs.
Signs include musty odors from supply registers, rooms that feel humid even when the AC runs, and higher-than-expected energy bills in mild weather when you shouldn’t need much conditioning. We confirm it with pressure testing and camera inspection. If your crawlspace smells like tide flats after rain and your ducts run through it, there’s a strong chance they’re part of the problem. We’ll show you the footage and give you a written price to fix it.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Burlingame and the Peninsula since 2004.