How Much Does Air Duct Replacement Cost in Seattle? [2025 Data]

Air duct replacement costs in Seattle commonly range from $618 to $2,104, with the average project costing about $1,250. Your overall cost will depend on the specifics of your ducts (including their type and location), as well as the size of your home. Let’s walk through these factors (and others) to help you create an accurate budget for air duct replacement in Seattle.

Air Duct Replacement Cost Factors 

To figure out how much you’ll spend on air duct replacement in Seattle, WA, you’ll need to consider the size and layout of your house and the type of ducts you’re installing.

Size

The size of your home directly affects air duct replacement costs. Larger homes require more materials and labor to replace the entire duct system. On average, the cost ranges from $2,000 to $5,000 for a small- to medium-sized home. However, duct replacement can run as low as $1,400 for smaller homes and as high as $9,000 for larger homes. Here’s how the size of your home affects duct replacement costs:

Duct Location

If only specific sections of your ductwork need replacement, such as in a renovation project, costs will depend on the location of the damaged or worn ductwork. Replacing ducts in hard-to-reach or concealed areas—like attics, basements, ceilings, walls, or crawl spaces—can increase labor costs. Here’s how the location of the ducts could affect their cost:

Duct Material

The material you choose for your replacement ducts affects both their cost and longevity. The most common types of ducts in Seattle, WA, are flexible and metal.

Sheet metal ducts are durable but pricey. Flexible ducts, on the other hand, are more affordable but may need to be repaired or replaced sooner. Here’s a breakdown of air duct replacement costs based on duct material:

HVAC Pro Costs

Before finalizing your ductwork replacement budget, you’ll want to factor in a few final costs, including permits and taxes.

Licensing and Certification

Replacing ductwork requires a specialized set of skills and HVAC knowledge, so it’s important to hire a licensed and insured HVAC pro in Seattle, WA, for this type of work. When you’re interviewing candidates, ask about their background, qualifications, and any other credentials (like NATE certification) to make sure they have the right experience for the job.

Permits

In Seattle, installing new mechanical equipment (such as heating and cooling systems) requires a mechanical permit. If permits are necessary for your project, your air duct installer should pull them for you and include the cost in their quote. 

Sales Tax

Seattle’s 10.35% sales tax will apply if you purchase your ductwork or other project materials in the city. It might not blow your budget, but it will bump up your costs—especially if you choose a pricier type of ductwork (like sheet metal).

Does Air Duct Replacement Increase Home Value?

As a standalone project, replacing your air ducts won’t increase your home’s value dramatically. However, for buyers, a house with new ductwork is more appealing than one with worn-out or inefficient ducts. Also, if you add new ductwork while replacing the rest of your HVAC system, you could see a bigger rise in your property’s resale value—about 5% to 7%.

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

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