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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AfterHow Much Does Duct Repair & Sealing Cost in Los Angeles?
Duct repair and sealing in Los Angeles typically costs $450 to $1,800 for most homes, with the average job landing around $850. Small single-point repairs like a disconnected joint or a torn flex run start near $250, while whole-home sealing of a 2,500-square-foot house with attic and crawlspace ductwork can reach $2,500 or more. Labor, access, and how much ductwork is buried behind drywall or under insulation drive nearly all of the spread.
We’re Cardinal Air Duct Cleaning, and we hand every Los Angeles homeowner a written price before we touch a single duct. No surprise line items at the door, no “we’ll see once we open it up.” That written price is part of how we run every job, and it’s backed by our 365-Day Done Right Promise.
Key Takeaways
- Most LA duct repair and sealing jobs run $450 – $1,800; whole-home sealing on larger homes can hit $2,500.
- Leaky ducts can waste 20% – 30% of the air your HVAC system produces, so sealing often pays for itself in energy savings.
- Rebates from LADWP and SoCalGas can offset part of the cost on qualifying efficiency upgrades.
- Every Cardinal job includes a written price before work starts, before-and-after photos, and our year-long guarantee.
Duct Repair & Sealing Cost Breakdown (2026)
Here’s what Los Angeles homeowners are actually paying across the most common repair and sealing tasks. These are real market ranges for 2026, not national averages pulled from a lead-gen site.
| Service | Typical LA Price Range | What It Covers |
|---|---|---|
| Single joint / connection repair | $250 – $500 | Reconnecting a separated or crushed run, sealing one leak point |
| Aeroseal-style whole-home sealing | $1,400 – $2,500 | Sealing 10 – 30% of leaks across the full system from the inside |
| Mastic + mesh hand sealing (per accessible section) | $450 – $1,200 | Physical sealing of accessible attic or crawlspace runs |
| Flex duct replacement (per run) | $200 – $450 | Replacing torn, kinked, or rodent-damaged flex duct |
| Rigid duct replacement (per section) | $350 – $900 | Rebuilding crushed or water-damaged sheet metal ductwork |
| Insulation wrap on exposed duct | $150 – $600 | Re-insulating attic runs to cut heat gain |
| Full system reseal + cleanout | $800 – $1,600 | Sealing plus cleaning, the standard combo most LA homes need |
What pushes the price up: ductwork that’s buried under blown-in insulation, runs crammed against HVAC equipment in a 110-degree attic, or a house with multiple zones where each zone has its own leak profile. What keeps it down: a single-story home with a clean, accessible attic and just a handful of disconnected joints. The repair itself is often the smaller cost; the access and the condition of the surrounding ductwork usually decide the final number.
If your ducts are also full of debris from the leak, we usually pair repair with a full cleaning. Our Duct Repair & Sealing in Los Angeles page walks through how we sequence cleaning before sealing so the seal actually holds.
What Affects Duct Repair & Sealing Pricing in Los Angeles
Duct pricing in LA isn’t the same as duct pricing in Phoenix or Phoenix-adjacent desert markets, and it isn’t the same as pricing on the East Coast. Here’s what actually moves the number in this city.
- Attic heat and duct location. Most LA single-family homes run flex duct through a vented attic. On a July afternoon in Woodland Hills or Reseda, that attic can sit at 130°F or higher. That heat cooks standard flex duct, which is why we see so many cracked inner liners and separated joints in the Valley compared to homes closer to the coast.
- Access difficulty. A crawlspace run under an Echo Park bungalow with 18 inches of clearance takes longer to seal than an open attic run. More time on the clock, higher labor cost. Restricted-access ductwork can add 20% – 40% to a sealing job.
- System age. Pre-1990 homes in neighborhoods like Highland Park and Boyle Heights often have original metal ductwork with failing tape and mastic. Older systems usually need more sealing points, sometimes replacement rather than repair.
- Number of leak points. A typical LA home loses 20% – 30% of conditioned air through leaks. The more leaks, the longer the job. A single-story home with 8 leak points is a very different quote from a two-story with a zoned system.
- Duct material. Flex duct is cheaper to repair or replace. Hard-piped sheet metal lasts decades but costs more per foot to build if a section needs rebuilding. Rigid ductwork also holds a seal better and needs less of it, so the trade-off usually balances out over time.
- Contamination. If a leak has been pulling attic air, dust, or pest debris into the system, the ducts need cleaning before sealing. Sealing over dirty ductwork traps the problem inside it, so we never skip that step.
How to Save on Duct Repair & Sealing in Los Angeles
Duct work isn’t glamorous, and nobody wants to spend more than they have to on it. Here’s how LA homeowners keep the number reasonable without cutting corners that come back later.
- Get the system sealed, not just patched. A $300 tape-and-go repair on one joint is a bandage. Whole-home sealing costs more upfront but fixes the actual air loss. We’ve seen homeowners spend $400 a year on three separate spot repairs when a single $1,500 sealing job would have ended the loop.
- Bundle sealing with cleaning. If you’re already having ducts cleaned, adding sealing on the same visit saves the trip charge and the setup. Bundling typically runs $200 – $400 less than booking the two separately.
- Check for utility rebates. LADWP and SoCalGas both run efficiency programs that can offset part of a qualifying duct sealing or insulation upgrade. Requirements change year to year, so confirm current eligibility before booking.
- Fix leaks before summer. Sealing in spring or early fall means we’re not working in a 130°F attic, and you’re not paying peak-season scheduling pressure. Same job, easier conditions.
- Ask for a written price before anyone starts. Every Cardinal Air Duct Cleaning job includes a written price before work begins. If a contractor won’t put the number in writing before opening your system up, that’s a sign the price is negotiable after the fact, and you don’t want to be on that side of it.
We offer free estimates across Los Angeles, so there’s no cost to get a real number before you decide. Call (737) 727-2314 and a live person will answer, day or night. We use Rotobrush brush systems, Nikro HEPA vacuums, and Abatement Technologies containment units on every job, and our technicians are background-checked and arrive in uniform.
FAQs – Duct Repair & Sealing Cost in Los Angeles
How much does duct sealing cost in Los Angeles?
Duct sealing in Los Angeles typically costs $450 to $1,800, with whole-home aeroseal-style sealing on larger homes running $1,400 to $2,500. The final number depends on how many leak points the system has and how hard they are to reach. Call (737) 727-2314 for a free estimate, and we’ll give you a written price before any work starts.
Is duct sealing worth the money in LA?
Yes, and the math usually works within a couple of years. A typical Los Angeles home loses 20% – 30% of its conditioned air through leaks, so sealing reduces both your energy bill and the strain on your HVAC system. On a home with a $250 monthly summer cooling bill, sealing often trims $30 – $60 a month during peak season. We back every sealing job with our 365-Day Done Right Promise: if the work isn’t right within 365 days, we return and correct it at no charge.
Can you repair my ducts the same day?
Often, yes. Most single-point repairs, disconnected joints, and simple flex duct replacements can be completed in a single visit. Whole-home sealing takes longer and may need a scheduled return depending on the size of the system. Call (737) 727-2314 and we’ll tell you what your specific job requires before we book it.
Is it cheaper to repair or replace my ductwork?
Repair is almost always cheaper in the short term, and it’s the right call for most systems under 15 years old with minor leaks. Flex duct replacement runs $200 – $450 per run, while rigid sheet metal replacement runs $350 – $900 per section. Full system replacement usually only makes sense when the ductwork has widespread rodent damage, water intrusion, or has already been patched multiple times. We’ll tell you honestly which one you’re looking at before you commit to anything.
Do you offer free estimates for duct repair in Los Angeles?
Yes. Cardinal Air Duct Cleaning offers free estimates on every duct repair and sealing job in Los Angeles. You’ll get a written price before any work begins, before-and-after photos when we’re done, and a digital invoice you can pay from a link. Call (737) 727-2314 and a live person will pick up, even at 2 a.m.
How long does duct sealing last?
Properly applied mastic and mesh sealing typically lasts 10 to 20 years, and aeroseal-style sealing is rated for a similar lifespan. Cheap foil tape fails in two to five years, especially in a hot Los Angeles attic where adhesive breaks down fast. That’s why we use professional-grade products and back the work with a written guarantee plus a free second visit if a repair fails.
Pricing reflects the Los Angeles market as of 2026. Cardinal Air Duct Cleaning offers free estimates – call (737) 727-2314.
Written by Omar Haddad, Owner at Cardinal Air Duct Cleaning, serving Los Angeles since 2005.
What Our Customers Say
"Booked a slot in the app, got a reminder text, and watched the crew's van on the map as it came. Cleaned all the vents and the main trunk. Easy from start to finish."
- Rob J."Cleaning plus HVAC coil clean. Tech texted when he was ten minutes away. No surprises on the price."
- Evan S."Dryer vent fix fixed the burning smell. The clog was behind the elbow and the whole laundry room smells normal now."
- Dennis K.