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 Big Bear City
Duct sealing in Big Bear City typically runs $450 – $1,200 for a whole-home system, with most cabin jobs falling in the $600 – $900 range depending on access and how much of the ductwork runs through unheated crawlspaces or attics. We’re the Duct Sealing team at Hollis Air Duct Cleaning, and we dispatch to Big Bear City from our Inland Empire office in Riverside-San Bernardino County. Crews carry mastic, mesh, foil tape rated for sub-freezing temps, and insulation wrap because mountain ductwork fails differently than low-elevation systems. Call (361) 326-5060 for a written estimate before any work starts.
Why Hollis Air Duct Cleaning Is Big Bear City’s Preferred Duct Sealing Company
We’ve been in business since 2004 as part of the Garrison Partners family, and our technicians know the difference between a tract home duct system and a 1960s A-frame with supply runs buried in a snow-loaded attic. Every tech is background-checked, uniformed, and held to The Garrison Code: arrive inside the quoted window, price in writing, complete the job by the book, leave the site clean.
Our 365-Day Done Right Promise applies to every sealing job in Big Bear City. If a seam we sealed fails within a year, we return and make it right at no charge, including a free second visit. No negotiation, no runaround.
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 around your vacation rental’s checkout time.
We serve Big Bear City and the surrounding mountain communities with the same equipment commercial crews use: Rotobrush rotary systems, Nikro negative-air machines, and filtration products from Aprilaire and Abatement Technologies. Not hardware-store gear.
Duct Insulation in Big Bear City
Duct Insulation in Big Bear City is often the companion job to sealing, because ducts that run through unheated crawlspaces and attics at 6,700 feet lose heat through the metal itself even when the seams are tight. We wrap sealed supply trunks and branch runs with formaldehyde-free fiberglass insulation jacket, then seal the jacket seams with foil tape rated for the temperature swings you see from October through April. A typical duct insulation job in Big Bear City runs $300 – $800 on top of sealing costs, depending on linear footage and whether we need to pull down ceiling panels or access a tight crawlspace.
Why Unheated Spaces Need It
Big Bear City’s freeze risk means a 120-degree supply duct sitting in a 25-degree attic sheds BTUs fast. Insulated ducts deliver air to your registers at the temperature your thermostat actually called for, instead of lukewarm air that makes your furnace run longer and your propane bill climb.
Vacation Rental Considerations
Owners of rentals near Snow Summit or along the south side of the valley often schedule insulation work during the Tuesday-to-Thursday gap between guest blocks. We price it in writing before we start, so your property manager knows the exact cost before the crew arrives.
HVAC Duct Sealing in Big Bear City
HVAC Duct Sealing in Big Bear City means finding and closing every leak in your forced-air system, from the air handler to the furthest register. We pressurize the ductwork, run a calibrated leakage test, then seal seams with mastic and fiberglass mesh on metal ducts or replace failing flex-duct connections where rodents have chewed through. A typical whole-home sealing job in Big Bear City costs $450 – $1,200, with simpler single-zone cabins on the low end and multi-story vacation rentals with attic and crawlspace runs on the high end.
The Freeze-Thaw Problem
Big Bear City sits at roughly 6,700 feet with freeze risk from October to April, so ducts routed through unheated crawlspaces and attics collect condensation that freezes and thaws, opening seams and pulling old foil-tape and mastic joints apart faster than they fail in low-elevation California towns. We see this every spring on the original 1940s – 1980s cabin ductwork that still serves homes off Knickerbocker Road and along the north slope toward Baldwin Lake.
What the Test Reveals
Our leakage test measures CFM25, cubic feet per minute of airflow at 25 pascals of pressure. A typical Big Bear City cabin built in the 1970s tests at 300 – 600 CFM25 before sealing and drops below 150 CFM25 after we finish. Below 150, you’re no longer heating your crawlspace instead of your living room.
Trusted Brands We Service in Big Bear City
We carry sealing and filtration products from Aprilaire, Abatement Technologies, and Guardsman on every Big Bear City truck, plus mastic and mesh rated for mountain temperature swings. If your system uses Honeywell media filters or an Aprilaire whole-house air cleaner, we stock replacement parts so you don’t wait for a second trip up the mountain. Our Rotobrush and Nikro equipment handles source removal before we seal, because sealing dirty ducts traps debris inside. Fast turnaround matters in a seasonal town where rental income depends on occupancy, and we schedule around your checkout-checkin window when needed.
Common Duct Sealing Problems We See in Big Bear City Homes
- Cracked mastic and failed foil tape on original cabin ductwork. The 1940s – 1980s homes that dominate Big Bear City’s housing stock were sealed with products that harden and split after decades of freeze-thaw cycles in unheated crawlspaces. We scrape off the old material and apply new mastic with fiberglass mesh that flexes with temperature change.
- Disconnected or crushed runs from rodent nesting. Pack rats and tree squirrels nest in ductwork over winter, especially on the south side of the valley closer to the national forest. We find chewed flex duct, shifted metal branches, and crushed main trunks behind air handlers that leak heated air into attics and crawlspaces.
- Condensation damage in unconditioned spaces. Cold attics and crawlspaces at 6,700 feet create temperature differentials that make duct metal sweat. Moisture rusts connections, loosens tape adhesive, and promotes mold growth that homeowners smell when the furnace first kicks on in October.
- Masked leaks in pollen-coated ducts. Long vacancies between vacation-rental guests let pine pollen, pine needles, and wood-smoke residue coat duct interiors. A quick visual check misses gaps because debris bridges them. We source-remove under negative pressure with HEPA filtration first, then test and seal.
Pricing for Duct Sealing in Big Bear City, CA
A typical whole-home duct sealing job in Big Bear City runs $450 – $1,200. Single-zone cabins with accessible crawlspaces usually fall at $600 – $750. Multi-story homes with attic and crawlspace runs, vacation rentals with complex branch ducting, or jobs requiring significant rodent-damage repair trend toward $900 – $1,200. Duct insulation adds $300 – $800 depending on linear footage.
What moves the number: how much ductwork runs through unheated space, whether we need to repair or replace crushed flex duct, and how many seams require mastic versus full section replacement. We do not quote per-vent teaser prices that balloon once the technician is inside. We give one flat price per system, agreed in writing before any work starts. Estimates are free. Call (361) 326-5060.
We Also Serve Cities Near Big Bear City
Our crews work throughout the San Bernardino Mountains and high desert fringe, including Big Bear Lake, Lucerne Valley, Running Springs, and Yucaipa. If your rental portfolio or primary home sits outside Big Bear City proper, we still price in writing and honor the same 365-Day Done Right Promise.
Serving Big Bear City, CA - Our Local Coverage Area
We’re based in the Big Bear City 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 Big Bear City
Yes, we specialize in sealing ducts in unheated crawlspaces and attics because that’s where most Big Bear City cabin ductwork fails. We apply mastic and fiberglass mesh rated for sub-freezing temperatures, then insulate the sealed runs so the fix survives the next freeze-thaw cycle. Call (361) 326-5060 for a free estimate.
If your registers blow weakly, your furnace runs constantly, or your propane bill spikes without thermostat change, you likely have leaks that cleaning alone won’t fix. We test duct pressure with a calibrated leakage test before recommending either service. Call (361) 326-5060 and we’ll diagnose it.
Sealing closes gaps that rodents use to enter ductwork, but if pack rats or squirrels have already chewed through, we repair or replace the damaged sections first. We use metal-reinforced materials where rodents are active, especially on homes near the national forest. Call (361) 326-5060 to schedule an inspection.
Yes, we schedule sealing jobs during your vacancy windows, typically Tuesday through Thursday between checkout and checkin. We arrive inside the quoted window, finish in one day for most cabins, and leave the site clean so your cleaner can prep for the next guest. Call (361) 326-5060 to book around your calendar.
Proper sealing improves airflow at your registers and reduces strain on your blower motor, because conditioned air reaches its destination instead of leaking into the attic. After sealing, we verify static pressure at the air handler to confirm the system operates within manufacturer spec. Call (361) 326-5060 with equipment-specific questions.
On a 1970s A-frame off the south side of the valley near the national forest, our tech ran camera inspection on the supply and return ducts and found a crushed main trunk behind the air handler plus three disconnected runs a pack rat had nested in over winter. After source removal under negative pressure with HEPA filtration, we sealed the seams with mastic and mesh, insulated the attic runs, and airflow at the far registers came back to spec. That’s the kind of job we do in Big Bear City, priced in writing before we start, backed by a full year.
Written by Roy Castellanos, Owner at Hollis Air Duct Cleaning, serving Big Bear City since 2004.




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