Fast, Reliable Duct Repair & Sealing Across North Hollywood
Duct repair and sealing in North Hollywood typically costs $180-$650 depending on whether you need spot sealing with mastic or full flex duct replacement, and most jobs are completed in a single visit. We serve the full 91605, 91606, 91609, and 91611 ZIP codes, including the Victory Boulevard corridor, the NoHo Arts District, and the apartment blocks near Saticoy and Lankershim. Our Duct Repair & Sealing team is usually on-site within 90 minutes for North Hollywood calls. If your airflow has dropped off or your upstairs rooms won’t cool, call (855) 401-6006 - we’ll send a technician with a camera and give you an upfront price before any work begins.
Why Bellows Air Duct & Vent Co. of California Is North Hollywood’s Preferred Duct Repair & Sealing Company
We’ve been working in the San Fernando Valley since 1984, and North Hollywood has become one of our most frequent Air Duct Cleaning - North Hollywood service areas. The combination of 1960s-70s housing stock and extreme attic heat creates duct problems we see nowhere else in greater Los Angeles.
Our North Hollywood customers know our technicians by the uniform and the camera. Every job gets inspected before and after, with photos shown to the homeowner. The 90-Day Done Right Promise is stamped on every invoice - if it’s not right, we come back at no charge, no paperwork, no arguing.
Calls from North Hollywood are answered by a live person, 24 hours a day. Not a voicemail. Not an app. A real person who can dispatch a background-checked, uniformed technician to your door, usually same day.
We know the local buildings. The two-story stucco complexes along Victory, the mid-century single-family homes tucked into the 91601 and 91602 pockets near the Arts District, the narrow crawl spaces and retrofitted attic systems that require specific expertise. Duct Repair & Sealing in North Hollywood isn’t a generic service here - it’s shaped by forty-two years of working in Valley conditions.
Our Duct Repair & Sealing Services in North Hollywood
Flex Duct Repair
Flex duct repair is our most common call in North Hollywood, and there’s a reason. The 1960s-70s apartment complexes that dominate ZIP codes 91605 and 91606 were built with attic-mounted central HVAC added during or after construction, often using flex ductwork that is now 30-50 years old. Valley attic temperatures routinely exceed 150°F in summer. That heat cooks the foil-and-plastic liner assemblies until they delaminate, collapse, or separate at the joints.
We responded to a call near Saticoy and Lankershim in a 1970s two-story stucco complex. The tenant reported weak airflow, and our tech found that the original flex duct inner liner had fully separated at a joint, dumping conditioned air into the attic. We performed flex duct repair using mastic sealant and new insulation, restoring proper airflow and sealing the leak. Camera documentation before and after showed the homeowner exactly what failed and what was fixed.
Typical flex duct repair in North Hollywood runs $280-$550 for spot repairs, $650-$1,200 for full branch replacement. We apply mastic sealant at every joint, wrap with fresh insulation, and verify with post-repair camera inspection.
Duct Sealing
Duct sealing in North Hollywood addresses the leakage that develops at joints, connections, and penetrations over decades of thermal cycling. The Santa Ana wind events of fall push additional desert dust and debris into attic spaces, and any gap in your ductwork becomes an entry point. We seal with professional-grade mastic and reinforced mesh, not tape that will dry and fail within a season.
Whole-system duct sealing for a typical North Hollywood apartment or single-family home runs $450-$850. We price by the linear foot and the number of junctions, and we show you the camera footage so you understand exactly where the leaks are.
Metal Duct Repair
Metal duct repair is more common in the mid-century single-family homes of 91601 and 91602, where galvanized steel trunk lines were sometimes used for original or retrofitted forced-air systems. These narrow crawl-space and attic runs corrode at the seams and can separate where supports have failed. Access is often the challenge in North Hollywood’s older homes - tight clearances, original framing, and retrofit work done without modern clearances.
Metal duct repair in North Hollywood typically runs $350-$750 for spot welding, patching, and resealing. Where access is severely limited, we may recommend transitioning to flexible connections in specific sections, which we discuss with you before any demolition.
Duct Insulation Replacement
Duct insulation in North Hollywood degrades faster than almost anywhere else we serve. The 150°F attic temperatures compress and break down fiberglass wraps, and the foil facing on flex duct insulation separates from the liner beneath. Once insulation fails, your cooled air warms before it reaches the register, and condensation forms on exposed metal in winter.
Insulation replacement for accessible trunk lines runs $180-$340 per branch in North Hollywood. We use materials rated for extreme temperature exposure, properly sealed at every penetration.
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 North Hollywood
We stock parts and materials from Abatement Technologies, Rotobrush, and Aprilaire - the same brands serious HVAC contractors specify for commercial and high-residential installations. For North Hollywood Dryer Vent Cleaning customers, this means we don’t order parts and make you wait. Our trucks carry mastic sealant, flex duct in standard diameters, insulation wraps, and connection collars sized for the 6-inch and 8-inch lines common in Valley apartment construction. Most repairs are completed in a single visit because we’ve already invested in the inventory this market demands.
Common Duct Repair & Sealing Problems We See in North Hollywood Homes
- Collapsed flex duct liners from sustained attic heat. The foil-and-plastic inner liners in 1960s-70s flex ductwork delaminate and collapse after decades above 150°F. What presents as weak airflow is often conditioned air dumping into the attic cavity through a separated liner. Our camera inspection finds these failures before we start any cleaning.
- Deteriorated joints in original 30-50-year-old flex ducts. The connection collars and zip-tie assemblies at branch junctions dry out and separate. North Hollywood’s extreme thermal cycling - hot attics, cooled air inside - accelerates this failure mode beyond what coastal LA buildings experience.
- Narrow crawl spaces making metal duct access difficult. Mid-century single-family homes in 91601 and 91602 frequently have crawl spaces or attics that were never designed for maintenance access. Metal duct repair in these conditions may require strategic demolition or retrofitting flexible connections in the most confined sections.
- Particulate loading from Valley air quality. The San Fernando Valley’s basin geography traps vehicle exhaust, wildfire smoke, and construction dust between the Santa Monica Mountains and Verdugo Hills. North Hollywood’s outdoor air carries a measurably heavier dust and soot load than coastal communities, which deposits inside ductwork and accelerates corrosion at seams and joints.
Pricing for Duct Repair & Sealing in North Hollywood, CA
We disclose every price before we lift a tool. No bait coupons, no changes at the door. Here’s what duct repair and sealing typically runs in North Hollywood:
| Service | Typical Range |
|---|---|
| Spot duct sealing with mastic (1-3 joints) | $180-$280 |
| Whole-system duct sealing | $450-$850 |
| Flex duct spot repair (single branch) | $280-$550 |
| Flex duct full branch replacement | $650-$1,200 |
| Metal duct repair / patching | $350-$750 |
| Duct insulation replacement (per branch) | $180-$340 |
Factors that affect your specific price: accessibility (attic vs. crawl space vs. enclosed soffit), extent of damage visible on camera inspection, and whether the system requires partial disassembly to reach the failure. We show you the camera footage and explain exactly what we found before we quote.
Standing offers apply: $50 off any repair over $250. Free second opinion on any written estimate from another company. Permanent 5% senior and veteran discount. Call (855) 401-6006 for a free estimate - the number we give you is the number on the invoice.
We Also Serve Cities Near North Hollywood
Our technicians live in the Valley and know the short cuts between calls. We also serve North Hollywood neighbors in Valley Village, Studio City, Universal City, and Burbank with the same 90-minute response commitment and same upfront pricing. The same attic heat and aging housing stock affect ductwork across these communities, and we carry the same inventory to handle them.
Serving North Hollywood, CA - Our Local Coverage Area
We’re based in the North Hollywood 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 North Hollywood
North Hollywood’s 1960s-70s apartment flex ducts fail because sustained attic temperatures above 150°F degrade the foil-and-plastic liner assemblies over 30-50 years, causing delamination, collapse, and joint separation that doesn’t occur in cooler coastal climates. The San Fernando Valley’s basin geography traps heat, and these buildings were constructed with attic HVAC retrofits using materials never designed for that thermal load. If your upstairs units barely cool while your downstairs overworks, call (855) 401-6006 - we’ll camera-inspect and show you exactly what the attic heat has done.
The signs are uneven cooling between floors, utility bills that spike in July and August without thermostat changes, and dust accumulation around ceiling registers. In North Hollywood’s two-story stucco complexes, we frequently find that conditioned air has been dumping into the attic for years through separated flex duct liners, with tenants simply adjusting thermostats higher to compensate. Our camera inspection documents the failure with photos you can show your property manager or keep for your records. Call for a free estimate - camera inspection is included.
Repair is often the right choice for localized failures - a separated joint, a collapsed section, or degraded insulation on an otherwise intact run. Full replacement becomes necessary when multiple branches show liner collapse, when the original duct diameter is undersized for current HVAC load, or when access is so poor that spot repairs won’t last. We give you camera evidence of the full system condition and price both options so you can decide. Most of our North Hollywood customers choose targeted repair with mastic sealing, which typically extends service life 10-15 years at roughly half the cost of full replacement.
Mastic is a thick, fiber-reinforced adhesive compound that remains flexible after curing, designed specifically for HVAC duct joints and penetrations. We use it instead of tape because North Hollywood’s extreme attic heat destroys standard duct tape within a single season - the adhesive dries, cracks, and fails. Mastic survives the thermal cycling that defines Valley conditions, and we apply it with mesh reinforcement at every joint we repair. It’s the standard specified by serious HVAC contractors for permanent sealing in high-heat environments.
Yes. Fall Santa Ana wind events push desert dust, debris, and fine particulates into North Hollywood attic spaces and through any existing duct gaps, accelerating buildup inside the system and increasing corrosion at metal seams. The winds also pressurize attic spaces differently, which can stress weak joints and separated liners. We inspect for wind-related damage during fall service calls and seal penetrations that would otherwise admit debris year-round. If you haven’t had your ducts inspected before Santa Ana season, call (855) 401-6006 - estimates are free.
Written by Roger Castañeda, Owner at Bellows Air Duct & Vent Co. of California, serving North Hollywood since 1984.