How Much Does Ductwork Cost?

Out of sight and often out of mind, it’s easy to overlook the ductwork when replacing your HVAC system – but it’s crucial not to. The condition of your ductwork can significantly impact your new system’s performance and the overall comfort of your home.

While new ductwork can add to the installation cost, it’s often necessary. HVAC.com explains why ductwork replacement should be a priority, how it affects your project’s cost, and the factors that influence the price.

Is Ductwork Replacement Always Necessary When Installing a New HVAC System?

It’s not always necessary to replace the ductwork when upgrading your heating and cooling system. The average lifespan of ductwork is typically 15 to 25 years, so depending on the ductwork’s age, condition, and other factors, it may be possible to keep your existing ducts. 

However, installing a new HVAC system without addressing problematic ducts can lead to issues and affect the performance and efficiency of your system. Here’s what you need to consider:

When to Keep Your Existing Ductwork

• Good Condition and Proper Sizing. If your existing ductwork is in good shape, properly sized for your new HVAC system, and free from leaks, you might not need to replace it. Well-maintained ducts can continue to perform efficiently, allowing you to save money on the overall cost of installing a new HVAC system.
• Minor Modifications. Sometimes, just a few minor modifications to the existing ductwork is all that’s needed to accommodate a new HVAC system. This can include sealing leaks, insulating ducts, or adjusting connections to ensure compatibility with the new unit. If the ductwork is generally in good shape, these adjustments can enhance performance without replacement.

When to Replace Your Ductwork

• Damage. If your current ductwork is damaged from corrosion, excessive wear and tear, or physical impacts, replacement may be necessary. Damaged ducts can lead to inefficiencies in air distribution, increased energy bills, and poor indoor air quality. In these cases, replacing the ductwork ensures that your new HVAC system operates optimally and efficiently.
• Incompatible Sizing. If you’re installing a new HVAC system with different sizing requirements than the old one, your existing ductwork may need to be replaced or modified. Ducts that are too small for a larger system or too large for a smaller unit can cause poor air distribution and system inefficiencies. Properly sized ducts are required for the new system to perform at its best.
• Outdated or Inefficient Duct Design. Older duct systems might have design flaws that affect efficiency. For example, outdated ductwork could have issues like excessive bends or inadequate insulation, leading to energy loss and uneven temperatures. Upgrading to a new, more efficient duct design can improve the overall performance of your new HVAC system and enhance comfort throughout your home.

How Much Does Ductwork Cost?

On average, new ductwork costs about $2,000 to $3,000 per ton of HVAC capacity. This means that the overall cost will depend primarily on your HVAC system’s size. 

• 2-Ton System: Expect to pay between $4,000 and $6,000 for new ductwork. This range reflects the cost of materials and installation for a smaller system suitable for smaller homes or specific zones with lower heating and cooling needs.
• 3-Ton System: For a medium-sized HVAC system, ductwork installation costs between $6,000 and $9,000. This range accounts for a standard setup in a typical home with moderate complexity.
• 4-Ton System: A larger HVAC system requires more extensive ductwork, with costs ranging from $8,000 to $12,000. This includes materials and installation for larger homes or those with more complex layouts.

Factors Influencing the Cost of Ductwork

Aside from the size of the new HVAC system, other factors that impact the cost of new ductwork include:

Installation Complexity

Installing ductwork in new construction homes is usually cheaper than retrofitting ducts in existing ones because the ducts can be easily accessed during construction. In existing homes, retrofitting often means working in tight spaces like crawl spaces, attics, or behind walls, which complicates the process. The existing layout may need custom modifications, such as cutting through walls or rerouting infrastructure, increasing labor costs due to the extra time and effort needed to navigate these obstacles.

Material and Quality 

The type of materials used for ductwork can also influence the overall cost. Depending on the specifics of your home, your options may include:

• Sheet Metal Ducts: Generally, sheet metal ducts last between 20 to 25 years. Made from galvanized steel or aluminum, they tend to be more expensive due to their durability and resistance to damage. These ducts often come with a higher price tag but offer long-term benefits like improved air quality and longevity.
• Flexible Ducts: Flexible ducts typically have a shorter lifespan, usually around 10 to 15 years. Made from a flexible plastic or metal coil covered in insulation, they can be more prone to damage and wear. However, they are generally more affordable than sheet metal ducts.
• Fiberglass Ducts: The cost of fiberglass ducts generally falls between that of sheet metal and flexible ductwork. They often last around 15 to 20 years. Fiberglass does a good job insulating, but it can break down over time, which might lead to problems with air quality and efficiency.

Local Labor Rates 

Labor rates vary by location. In areas with higher costs of living or where skilled HVAC professionals are in high demand, labor costs can be significantly higher. Conversely, in regions with lower labor costs, ductwork replacement might be more affordable.

Additional Features 

Some ductwork installations may include additional features, such as dampers or zoning systems, which can also affect the overall cost of the project. These features enhance the efficiency of your HVAC system by allowing for better control over air distribution and temperature regulation, but they also add to the initial expense.