The average cost to replace HVAC ductwork is around $285 per duct run, and it is determined by the number of HVAC duct runs to be replaced, the length of each run, the type and size of the replacement ductwork, and other factors. When solid ducts in walls and ceilings need to be replaced, the cost per run can reach $550 or higher.
Removal of old duct and supply register, installation of new flexible or metal duct, labor costs, and disposal of all old materials are all included in the typical duct replacement cost range of $175 – $400 per duct replacement Houston.
A Summary of Central HVAC Duct Work Replacement Costs
There are two primary reasons for replacing ductwork.
- It’s possible that the old ductwork is in such bad shape that repairing it isn’t a good idea. Old ducts can leak up to 35% of the treated air, resulting in waste and higher-than-necessary energy costs. Some rust because of condensation forming in them over time.
- The previous HVAC system was far too large for the house. Contractors used to believe that bigger was better, but that is no longer the case. A large system wastes energy causes temperature fluctuations and does not adequately dehumidify a home in the summer.
Even if the old system was the correct size, upgrades such as house wrap, energy-efficient windows, and increased attic insulation reduce the need for heating and air conditioning capacity, resulting in a smaller next HVAC system. This could lead to a demand for smaller ductwork.
Price gouging should be avoided! “Across the country, gross profit margins for duct renovation work range from 65 percent to 80 percent.” According to Rob Falke, President of the National Comfort Institute, a company that helps HVAC companies improve their business, “that’s pretty sweet compared to the industry averages of 30 percent to 40 percent gross profit for equipment replacement.”
Given the large margins, it makes sense to get estimates from at least three companies in your area that have a good reputation for dealing with customers fairly and providing high-quality workmanship.
The remainder of this estimate includes cost factors, itemized pricing, and ductwork installation price estimates from other estimating websites. There’s advice on DIY duct installation as well as prices from homeowners who’ve recently had their ductwork replaced.
Factors Affecting Duct Prices
Ductwork replacement costs range from less than $1,000 to more than $6,000. Here are the factors that will determine where your project falls within that range.
- Type of Ductwork System – A radial system of flexible ducts in an attic running to ceiling grates is the least expensive duct system. Ductwork running along an open ceiling in a one-story home’s basement is also less expensive to replace. Sheet metal ducts running through enclosed walls and ceilings are the most expensive. Most projects necessitate the use of more than one type of ductwork.
- Size of Your Home – Larger homes necessitate more linear feet of ductwork, which raises the cost.
- Return Ducts – Return ducts are common in most homes. Some homes with open floor plans and a first-floor HVAC system don’t need them because air can be easily drawn back to the furnace or air handler.
- Number of Duct Runs – The size of your home is important, but so is the layout of your home. A sprawling ranch may have more duct runs than a two-story with the same square footage.
- Insulated duct R-value – Flexible ductwork running in open space, such as an attic, will be insulated from R6 to R10. The higher the R-value, the more expensive the ducting. However, this is a cost that quickly pays for itself, so choose higher R-values when given the choice. Nota bene: Increasing the insulation in your home is always a good way to save money on energy costs in all seasons. Examine spray foam insulation costs as well as traditional blown-in insulation costs to get a sense of cost versus savings.
- Wall/ceiling Disruption – As previously stated, when drywall or drop-ceiling systems must be removed and replaced, the cost estimate will be near the top of the range. This is more common in homes with multiple levels.
- Mold Remediation – If the crew discovers significant levels of mold in the wall space, it should be treated. Mold remediation, while uncommon, can be costly. If it is extensive, the costs will exceed the range given above. That’s a completely different project.
- Zoning Equipment Inside Ducts – The cost of removing and replacing dampers increases due to the additional materials and labor required.
- The complexity of the Ducting – Other factors that come into play here include house size and layout, where the ductwork is located, the age of the house and ducts, and so on.
- Time of Year – The HVAC contractors’ bids will most likely be affected by how busy or slow they are at the time you get estimates.
Installation Materials Cost
The following are the itemized costs for the most common types of ductwork and the supplies required for installation.
- $1.10 – $5.25 per foot | Insulated flexible duct with diameters ranging from 4″ to 16″ used as branches or in radial duct attic systems
- $2.30 – $13.00 per foot | Round and oval sheet metal duct with diameters ranging from 3″ to 8″ is commonly used for trunks in small homes and branches in larger homes.
- Rectangular duct | $6.50 – $12.00 per foot Trunks ranging in size from 6″x12″ to 12″x24″.
- $3.00 – $12.50 per foot | Spiral, decorative duct used where visible, such as along a loft apartment’s ceiling.
- $5.25 – $7.00 per square foot | Wall-mounted duct stacks
- Plenum is used to connect the furnace or air handler to the supply ducts, and Cold Air Drop is used to connect the return ducts to the furnace/air handler.
- Fittings and accessories such as boots, take-offs, joist pans, and dampers range in price from $225 to $575.
- $50–$125 | Duct sealant (tape, insulating wrap, and mastic)
- $60 – $200 | Depending on the quality of the tools
Costs of Permits, Inspection, and Unit Installation
It is unusual for a permit to be required for duct replacement. However, always check with your local codes.
Factors Affecting Installation Labor
Do-it-yourself ductwork saves money on labor. Check out our recommendation below to see if ductwork installation is a do-it-yourself project.
- $4.50 – $8.25 per foot
The cost of installation labor varies depending on the type, complexity, location, and how easy/difficult it is to access.
A variety of scenarios, installing ductwork can take anywhere from one to four days. In a single-story home, connecting an attic air handler to ceiling ducts is a simple project. Sice wall stacks are included, installing ducts in a multistory home takes longer.
Here’s an example of a 2,000 – 2,500 square foot two-story.
- Half a day to 1 day – expose and remove old ductwork
- 1 to 2 days – install new ducts
- Half a day to 1 day to seal new ducts and finish the project
- Total time = 2-4 days.