How Much Does It Cost to Replace Duct Work?

As a home improvement professional with years of hands-on experience at Miller Attics, one of the most frequent questions I hear from homeowners is, “How much does it cost to replace duct work?” It’s a vital question, as the ductwork is the respiratory system of your home, delivering conditioned air to every room. The answer, however, isn’t a single number. The cost is a spectrum, influenced by your home’s size, the system’s complexity, accessibility, and the materials used.

Understanding these variables is the first step toward budgeting for this crucial home improvement project. This article will serve as your professional guide, breaking down the factors that determine the final price, exploring the differences between repair and replacement, and highlighting the significant benefits of investing in a new duct system. Knowing what’s involved will help you see beyond the initial price tag and understand the long-term value for your home’s comfort and efficiency.

The True Cost: Deciding Between Ductwork Repair and a Full Replacement

Before you can accurately estimate how much does it cost to replace duct work, you must first determine if a full replacement is necessary. Sometimes, a targeted repair is all you need. In our experience, if your ducts are over 15-20 years old and showing multiple signs of failure, replacement is often the most financially sound decision for the long haul. While sturdy sheet metal ducts can last decades, the flexible ducts common in many homes can become brittle and inefficient after about 15 years.

When is AC Duct Repair or Air Duct Repair the Right Call?

A simple air duct repair is often sufficient for isolated problems. If you have a single disconnected line, a small tear from an accident in the attic, or a localized leak, a professional can often resolve the issue without overhauling the entire system. Common repairs include:

• Sealing Leaks: Using mastic sealant or specialized foil tape to patch small holes or joint separations. This can cost between $200 and $500.
• Replacing a Section: If one or two branches of your ductwork are crushed or damaged, a targeted replacement of those sections might cost $300 to $800.
• Reconnecting Ducts: Sometimes ducts simply become disconnected from a vent boot or plenum, a straightforward fix for a professional.

However, if you’re facing systemic issues, the conversation shifts from simple ductwork repair to a full replacement. These tell-tale signs indicate that a replacement is likely the more effective and economical option:

• Significant and Widespread Damage: Visible corrosion, numerous leaks, mold growth, or ducts that are tangled, crushed, or damaged in multiple areas.
• Poor System Performance: If you experience weak airflow, drastic temperature differences between rooms (hot and cold spots), or your HVAC system runs constantly, it often points to improperly sized or failing ducts. This is a key factor influencing how much does it cost to replace duct work, as a new system must be properly sized.
• Poor Indoor Air Quality: A sudden increase in dust, musty odors, or allergy symptoms can mean your ducts are circulating contaminants throughout your home.
• Old and Inefficient Design: Many older homes have ductwork that was designed only for heating. These systems are often too small to handle the higher airflow volume required by modern central air conditioning, making an ac duct repair ineffective and a full replacement necessary for a new HVAC unit to function properly.

The Ductwork Replacement Process Explained

A professional ductwork replacement is a methodical process that ensures your new system delivers optimal performance, safety, and efficiency. Attempting this as a DIY project can lead to poor performance, safety hazards, and potentially voiding your HVAC equipment warranty. Each step is critical and contributes to the final answer of how much does it cost to replace duct work.

1. System Inspection and Design: The process begins with a thorough inspection. At Miller Attics, we don’t just look; we measure. We perform calculations based on the Air Conditioning Contractors of America (ACCA) Manual D standard. This determines the precise duct size needed for each room’s required airflow (CFM), considering your home’s layout, window placement, and insulation. This scientific approach prevents ducts from being too small (which causes noise and strain) or too large (which leads to poor airflow and inefficiency).
2. Material Selection: Based on the design and your budget, we select the right materials. Options include durable but more expensive sheet metal, insulated fiberboard, or flexible ducts, which are ideal for navigating tight or complex spaces.
3. Removal and Installation: Our team carefully removes the old, failing ductwork. We then fabricate and install the new system according to the custom design. Every joint, seam, and connection is meticulously sealed with mastic or UL-181-rated tape. This step is non-negotiable, as leaky ducts can waste up to 30% of your conditioned air.
4. Insulation and Testing: Any ducts running through unconditioned spaces like your attic or crawlspace are wrapped with insulation of the proper R-value for our climate. This prevents energy loss and condensation. Finally, we test the system to ensure balanced airflow to every room.

How Much Does It Cost to Replace Duct Work? A Detailed Breakdown

Now we arrive at the central question. On average, homeowners can expect to pay between $25 and $55 per linear foot for a full ductwork replacement, including materials and professional labor. For a typical single-family home, the total project cost usually falls somewhere between $1,400 and $5,600.

However, this is just a baseline. When homeowners ask us at Miller Attics, “how much does it cost to replace duct work?“, we explain that the final price depends heavily on a few key variables:

• Home Size and Layout: A larger, multi-story home naturally requires more ductwork and more labor than a small, single-story home, increasing the overall cost.
• Accessibility: This is a huge factor. Ductwork in an open basement is the easiest and most affordable to replace. Working in a cramped, hot attic is more difficult and time-consuming, while navigating a tight crawlspace is the most challenging and therefore the most expensive scenario.
• Material Type: As mentioned, the cost of materials varies. Flexible ducting is the most budget-friendly, while rigid sheet metal is the premium option known for its longevity and durability.
• Extent of the Work: A quote may also include costs for removing and disposing of the old ductwork, repairing drywall or ceiling access points, and securing necessary permits, which can range from $250 to $1,500.

If hazardous materials like asbestos or significant mold are discovered, remediation will be required before any new work can begin, which can add $2,000 or more to the project. This is why a professional inspection is so important before work begins.

The Long-Term Value: Why New Ductwork is a Smart Investment

While homeowners understandably focus on the upfront question of how much does it cost to replace duct work, it’s equally important to consider the powerful return on that investment. New, properly sealed and sized ductwork is not just a repair; it’s an upgrade to your entire home.

• Dramatically Improved Energy Efficiency: By eliminating leaks, you ensure that nearly all the heated or cooled air your HVAC system produces actually reaches its destination. This can lower your heating and cooling bills by up to 30%, providing significant year-over-year savings.
• Enhanced Home Comfort: A professionally designed duct system eliminates frustrating hot and cold spots. It delivers balanced, consistent temperatures to every corner of your house, creating a more comfortable living environment for your family.
• Healthier Indoor Air Quality: Old ducts are notorious for collecting dust, dander, pollen, and even mold. A new, clean system provides fresh, filtered air, reducing allergens and irritants and creating a healthier home.
• Extended HVAC System Lifespan: When your ductwork is efficient, your furnace and air conditioner don’t have to work as hard to maintain the desired temperature. This reduced strain leads to less wear and tear, potentially extending the life of your expensive HVAC equipment.

Ultimately, replacing your ductwork is a powerful investment in your home’s efficiency, comfort, and health. If you have any concerns about your current system, don’t hesitate to reach out to a professional. Contact us at Miller Attics today for a comprehensive inspection and a precise quote tailored to your home’s unique needs.