HVAC Ductwork Cost: What It Really Costs to Install or Replace Ducts in Los Angeles

Updated: October 6, 2026

HVAC ductwork can cost anywhere from $1,500 to over $20,000, and that huge spread comes down to one question most homeowners never ask before getting quotes: which of three completely different scenarios applies to you. Installing ducts in a new build, retrofitting a house that never had any, and replacing worn-out ductwork are three separate projects with three separate price tags.

Three Scenarios, Three Different Budgets

The scenario you’re in determines your price range more than almost any other factor.

HVAC Ductwork Cost — By Project Scenario

The cheapest scenario is installing ductwork during new construction, since there are no existing walls, ceilings, or finished spaces for the designer to work around. Installing ductwork in an already-built home with none is typically the most expensive of the three, because it requires cutting into walls and ceilings to route ducts through a structure that was never designed for them. Removing and disposing of old ductwork during a replacement is its own separate cost on top of new material pricing. Before comparing prices between contractors, confirm which of these three scenarios their quote is actually built around.

Cost by Material — and Why It Shifts the Price 3–4x

Material choice is one of the biggest levers on ductwork pricing.

Ductwork Cost by Material Type

Material choice can shift the price per linear foot by three to four times between the cheapest and most expensive options. Most real-world systems actually use a combination: rigid metal or fiberboard on long, straight trunk lines, and flexible ductwork on short branch runs and tight, hard-to-reach spaces. Uninsulated ductwork running through unconditioned spaces — an attic or garage — can lose 10–15% of heating and cooling energy before it ever reaches a room, a real efficiency cost that factors into whether cheaper material is actually the better long-term value.

Cost by Home Size

Ductwork Cost — By Home Size

Most homes between 1,300 and 2,500 square feet fall within $2,500 to $6,700 for a full ductwork replacement. This is a planning benchmark, not a finished estimate — duct accessibility (a tight attic, a cramped crawlspace, a finished basement) can push the real price above what square footage alone would suggest.

What Drives the Price Up or Down

• Accessibility — attics run 2,200–5,600, basements 1,800–3,100, crawlspaces 3,000–7,300, and ductwork running through walls or ceilings 1,000–4,000.
• System complexity — multiple zones or a custom layout require more design time and equipment than a simple single-zone system.
• Regional labor market — in expensive coastal metros, including California, pricing runs 20–25% above the national average.
• Local building codes — California projects must comply with the Title 24 Energy Code (energy.ca.gov), which can add insulation and sealing requirements.
• Permits — fees range from under $100 to several hundred dollars depending on the local jurisdiction.

Duct accessibility determines labor time and cost more directly than almost any other factor on this list — a crawlspace job and an open-attic job with identical linear footage can carry very different price tags purely because of how hard the space is to work in.

Additional Costs — and the Full Scope of a Real Project

Beyond materials and labor, several line items commonly show up on real ductwork projects that aren’t part of the base estimate.

• Wall and ceiling repair after cutting access for ductwork — priced by actual scope of work
• Old ductwork removal and disposal — a separate labor charge reflecting the work involved
• HVAC equipment upgrades when existing equipment is incompatible with new ductwork — priced as needed
• Asbestos removal (relevant in older homes) — can add $2,000 or more
• Mold remediation if discovered inside old ductwork during removal

Budget an additional 10–15% above the base estimate for unforeseen costs common to projects that involve cutting into walls and ceilings.

Signs You Need Replacement, Not Repair

Repair usually makes sense for ductwork under 10 years old with only localized damage.

Signs pointing toward full replacement:

• Significant air leaks throughout the system, not just at one point
• Corrosion or physical damage to duct sections
• Uneven temperatures between rooms that don’t respond to thermostat adjustments
• Severely damaged or missing insulation
• Ductwork 15–20+ years old with recurring problems

A single pinhole leak, a loosened joint, or a small dent is typically fixed with targeted repair rather than full replacement. Extensive leaks throughout the system, or widespread corrosion affecting multiple sections, point toward systemic wear that repair alone won’t resolve long-term. Schedule an inspection with a licensed technician before deciding between repair and replacement on your own.

DIY vs. Professional Installation

Full ductwork installation is not considered a DIY-friendly project. It requires real technical knowledge — calculating proper airflow (measured in CFM), sealing joints correctly, meeting local building code requirements, and sizing ducts correctly to match a specific HVAC system’s output. Improperly installed ductwork reduces system efficiency and leads to uneven heating and cooling between rooms — exactly the kind of comfort complaint a full replacement is supposed to fix, not cause.

Leave full installation or replacement to a licensed specialist. DIY work is reasonable for minor sealing repairs, but not for designing or installing an entire duct system.

HVAC Ductwork Installation for LA-Area Homes

Pricing for ductwork work here generally tracks the ranges above, with California’s Title 24 Energy Code (energy.ca.gov) shaping insulation and sealing requirements for any new installation.

Before committing to a full replacement, our team providing HVAC services in Glendale can run a complete system assessment to confirm whether replacement is actually necessary or whether targeted repair would solve the problem. If an inspection shows only localized damage, our HVAC repair team addresses the specific issue directly, often at a fraction of full replacement cost.

Cold Cloud Mechanical serves Los Angeles, Glendale, and the surrounding communities.

Getting an Accurate Quote

The price ranges throughout this guide are a solid starting point, but the exact cost for your home depends on an in-home inspection — ductwork accessibility, current condition, and overall home layout all factor into the real number.

Ask for a detailed estimate broken down into materials, removal, and installation. For a straight, honest number specific to your home, reach out to Cold Cloud for a free on-site assessment and written quote.

Standards & Sources:

• California Energy Commission, Title 24 Building Energy Efficiency Standards — energy.ca.gov
• U.S. Department of Energy, residential HVAC ductwork efficiency guidance — energy.gov
• ENERGY STAR, HVAC system maintenance and duct sealing guidance — energystar.gov

Author Alex Butakov

Co-founder, CEO & Technical Director at Cold Cloud Mechanical, a Daikin Comfort Pro dealer and licensed C-20 and C-38 HVAC contractor serving Greater Los Angeles.