Fast, Reliable Duct Repair & Sealing Across Los Angeles
Duct repair and sealing in Los Angeles typically costs $280-$650 for most residential jobs, with same-day or next-day service available throughout the metro area. Call (855) 401-6006 for a free estimate with upfront pricing.
We’ve been working in Los Angeles homes since 1984, and we know the territory. From the tight attic retrofits in Los Feliz to the original fiberglass duct board crumbling in 1960s San Fernando Valley tract houses, our Duct Repair & Sealing team has handled the specific failures this city’s housing stock produces. Los Angeles presents a unique set of duct problems: Santa Ana winds driving ash and particulate through compromised seals, earthquake-shifted metal joints working loose over decades, and flex ducts in hillside homes disconnected by vibration and thermal cycling. We’re familiar with alley-load access in Koreatown townhomes, parking constraints in Silver Lake, and the security-conscious homeowners throughout View Park-Windsor Hills who want technicians they can verify. Our background-checked, uniformed crews carry mastic sealant, proper insulation materials, and camera inspection gear on every truck. Most repairs are finished in a single visit.
Why Bellows Air Duct & Vent Co. of California Is Los Angeles’s Preferred Duct Repair & Sealing Company
Los Angeles homeowners have called us back for forty-two years because we show up when we say we will and we stand behind the work. Our 90-Day Done Right Promise is stamped on every job: if it’s not right, we return at no charge, no paperwork, no arguing. That guarantee has been tested through Santa Ana wind seasons, after wildfire events, and across thousands of Valley and Westside homes.
Our reviews from Los Angeles customers consistently mention the camera inspection - they see the crack in the duct board, the disconnected flex joint, the ash film coating the return trunk before we touch a tool. That transparency matters in a market where bait-and-switch pricing is common. We disclose every cost before work begins. The number on the phone is the number on the invoice.
Response time to Los Angeles addresses averages same-day for calls received by early afternoon, next-morning for later calls. Our dispatchers are live people, 24 hours a day, not an app or voicemail tree. They know that a foothill home in Woodland Hills or La Cañada Flintridge may need priority scheduling after a wind event, and they route accordingly.
Local knowledge builds trust. We know that pre-war Spanish Revival homes in Silver Lake and Echo Park often had central air retrofitted into attics never designed for ductwork, creating chronic leak points at penetrations. We know that Reseda and Granada Hills tract homes from the Johnson and Nixon administrations are hitting critical failure age for original duct materials. This isn’t generic HVAC knowledge - it’s Los Angeles-specific field experience accumulated since 1984.
Our Duct Repair & Sealing Services in Los Angeles
Duct Sealing with Mastic Sealant
Mastic sealant is the only permanent solution for metal duct joints in Los Angeles. Duct tape fails within months here, degraded by Santa Ana wind-driven pressure cycling and the thermal expansion of earthquake-country frame construction. We brush or trowel water-based mastic into every longitudinal seam, transverse joint, and penetration point, then reinforce with embedded mesh on high-stress areas. The result survives pressure testing and holds through fire season. For Los Angeles homes near wildfire-prone foothills, sealed ducts also block the infiltration path for ash and combustion particulate when outdoor air quality crashes.
Flex Duct Repair
Flex duct is common in Los Angeles attic retrofits and hillside additions where rigid metal won’t navigate tight framing. It fails at connection points, where the inner liner separates from the collar, or where insulation sags and exposes the core to attic temperatures exceeding 140 degrees. We repaired a severed flex duct in a Silver Lake attic where a previous handyman had simply taped over a disconnected joint, drawing in unconditioned, contaminated air. Using mastic sealant and thermal insulation, we restored seal integrity and airflow, eliminating the dust and odor issues that had plagued the second floor. Our flex repairs include proper support strapping every four feet to prevent future sagging.
Metal Duct Repair
Galvanized steel ductwork in older Los Angeles homes corrodes at seams where condensation collects, particularly in beach-adjacent neighborhoods with salt air infiltration. Earthquake movement works hangers loose and cracks welded joints. We section-replace corroded trunk lines, re-hang sagging runs with proper vibration-isolated supports, and seal all connections with mastic rather than foil tape. For homes in Mid-City and Koreatown with original 1940s-50s metal systems, we evaluate whether spot repair or selective replacement makes economic sense, and we show you the camera footage before you decide.
Duct Insulation
Uninsulated or degraded duct insulation wastes conditioned air into Los Angeles attics that regularly exceed 120 degrees in summer. We install new foil-faced fiberglass insulation on repaired or replaced duct sections, sealed at all seams with matching tape and mastic. In tight Los Angeles attic spaces - the kind common in Los Feliz retrofits where a 24-inch crawlspace is generous - we use pre-formed insulation sleeves and flexible application tools to reach areas conventional crews skip. Proper insulation pays back fastest in the San Fernando Valley, where summer cooling loads are extreme and winter Santa Ana events create rapid temperature swings.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Los Angeles
We stock parts and specify equipment from Abatement Technologies, Rotobrush, and Aprilaire - the same brands serious HVAC contractors in Los Angeles use for remediation and sealing work. Abatement Technologies’ HEPA containment and negative-air systems protect your home during duct board removal in tight Valley attics. Rotobrush mechanical cleaning tools reach past compromised seals to prepare surfaces before mastic application. Aprilaire media air cleaners and whole-house dehumidifiers integrate with sealed duct systems for homeowners in foothill zones fighting wildfire-ash infiltration. We don’t order parts from out of state and make you wait. Our Los Angeles warehouse carries standard sizes and sealants for same-day completion on most residential jobs.
Common Duct Repair & Sealing Problems We See in Los Angeles Homes
- Duct tape used instead of mastic on metal and flex joints, failing within months under Santa Ana wind-driven pressure changes. We find this on nearly every callback from a non-specialist repair. The tape dries, cracks, and peels, leaving the joint open to attic air infiltration and pressure loss. Mastic is the only code-appropriate sealant for permanent repair in Los Angeles’s climate.
- Return-air grilles in foothill neighborhoods like Woodland Hills pack with ash after wind events, coating duct interiors with corrosive fine particles if not inspected. After Santa Ana wind episodes, technicians serving Tarzana, Woodland Hills, La Cañada Flintridge, and Sylmar know to inspect outdoor air intakes immediately: ash and ember debris pack into return-air grilles and coat duct interiors with a fine gray film containing structural combustion byproducts - a contamination event that clients’ standard annual cleaning schedules are never timed to catch.
- Original fiberglass duct board in Valley homes crumbles into ducts, releasing fibers that standard cleaning cannot remove without sealing or replacement. The San Fernando Valley’s dense 1960s tract homes in Reseda, Canoga Park, and Granada Hills often have original fiberglass duct board that deteriorates after 50+ years, shedding airborne fibers into the air supply. Cleaning alone dislodges more material. We assess whether encapsulation, section replacement, or full system upgrade is warranted.
- Disconnected flex ducts in hillside and retrofit homes, hidden above drywall and leaking conditioned air for years. Los Angeles’s steep hillside construction and pre-war retrofits often route flex duct through inaccessible soffits and chases. A disconnected joint can waste 30% of system airflow without any visible symptom except high utility bills and uneven temperatures. Camera inspection locates the failure without destructive access.
Pricing for Duct Repair & Sealing in Los Angeles, CA
Honest pricing means numbers before we start, not after we finish. Here’s what duct repair and sealing costs in the Los Angeles market:
- Flex duct section repair or replacement: $280-$420
- Metal duct seam sealing with mastic (per section): $180-$340
- Fiberglass duct board section replacement: $450-$780
- Duct insulation replacement (per linear foot): $8-$14
- Full system seal and pressure test: $650-$1,200
- Return-air grille and intake cleaning after ash contamination: $150-$280
Costs run higher in Los Angeles than inland markets for several real reasons: tighter attic access requiring specialized equipment, higher material transport costs to hillside and canyon addresses, and the additional containment procedures for wildfire-ash-contaminated systems. We apply our standing $50 Off Any Repair Over $250 to qualifying jobs, and we honor our permanent 5% Senior and Veteran discount. Every estimate is free, presented in writing, and fixed before work begins. Call (855) 401-6006 for your specific quote.
We Also Serve Cities Near Los Angeles
Our service territory covers the full Los Angeles basin and surrounding foothill communities. We regularly dispatch to Duct Repair & Sealing in Los Angeles proper plus Koreatown, Echo Park, Silver Lake, and View Park-Windsor Hills. Same scheduling, same upfront pricing, same 90-Day Done Right Promise applies across all service areas.
Serving Los Angeles, CA - Our Local Coverage Area
We’re based in the Los Angeles 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 - Duct Repair & Sealing in Los Angeles
Inspect within 48-72 hours after Santa Ana winds subside, particularly if you live in foothill-adjacent neighborhoods. Ash and ember debris pack into return-air grilles and coat duct interiors with a fine gray film containing structural combustion byproducts - a contamination event that standard annual cleaning schedules are never timed to catch. We offer post-wind-event inspections with camera documentation, and we can clean and seal intake paths to reduce future infiltration. Call (855) 401-6006 to schedule - estimates are free.
Original fiberglass duct board in Reseda, Canoga Park, and Granada Hills homes is typically at or past end of useful life after 50+ years, and aggressive cleaning often accelerates fiber release. We camera-inspect first to assess structural integrity. If the board is crumbling or delaminating, section replacement or full system upgrade is the only safe option. Where the material is intact but aged, encapsulation sealing may extend service life. We’ll show you the footage and explain your options with fixed pricing for each path. Call (855) 401-6006 for a free assessment.
Yes. We work in attics as tight as 18-24 inches of clearance, common in Los Feliz, Silver Lake, and Echo Park retrofits where central air was added to pre-war construction. Our crews use low-profile application tools, flexible mastic brushes, and section-by-section sequencing to complete seals without requiring full attic access. Camera inspection confirms coverage in areas we cannot physically reach. We’ve completed hundreds of these retrofits across Los Angeles’s older neighborhoods.
Some policies cover duct cleaning and sealing after documented wildfire ash infiltration, but coverage varies by carrier and requires specific documentation of contamination source. We provide detailed camera inspection reports, particulate testing referrals, and written scope-of-work documentation that insurance adjusters in Los Angeles recognize from previous Woolsey, Thomas, and Eaton fire claims. We do not negotiate with insurers directly - that’s your role or your adjuster’s - but we supply the technical evidence you need. Call (855) 401-6006 to start documentation.
Water-based mastic sealant with embedded reinforcement mesh is the only seal appropriate for permanent metal duct repair in Los Angeles’s seismic environment. Duct tape, foil tape, and caulking all fail within months to a few years under the thermal cycling and frame movement that earthquakes and Santa Ana wind pressure changes produce. Mastic remains flexible, adheres to galvanized steel and aluminum, and is rated for the temperature range of residential HVAC. We apply it to every metal joint we touch, and we pressure-test to verify. Call (855) 401-6006 for an estimate - we’ll show you the difference on camera.
Ready to fix the leaks, seal the joints, and stop wasting conditioned air? Call Bellows Air Duct & Vent Co. of California at (855) 401-6006 for a free, no-obligation estimate. We’ll camera-inspect your system, explain what we find in plain language, and give you one honest price before any work begins. Most repairs are completed in a single visit, and every job carries our 90-Day Done Right Promise in writing.
Written by Roger Castañeda, Owner at Bellows Air Duct & Vent Co. of California, serving Los Angeles since 1984.