This duct insulation guide discusses the reasons, materials and duct insulation costs. Most duct insulation is a two-piece product. The insulation is fiberglass made from spinning molten glass or stone wool made from spinning molten slag. The insulation is then faced with an aluminum heat and moisture barrier. Unfaced duct insulation is also available.
Duct insulation is also known in the industry as HVAC insulation since it contributes to the efficiency of the HVAC (Heating, Ventilation, Air Conditioning) system.
The material is produced in the form of a blanket for wrapping round and rectangular ducts to prevent heat loss or gain through the sheet metal and seams. Duct insulation is a cost-effective way to reduce heating and cooling bills and control humidity in your home throughout the year.
Reasons to Insulate the Duct Work
Energy experts from the US Department of Energy state that about 20% of the treated (heated or cooled) air that moves through ducts in your home is “lost due to leaks, holes, and poorly connected ducts.” That’s a significant waste or energy and money. Adding insulation to ducts will make them much more efficient when heating or cooling your home.
A second reason to consider insulating your ducts is the control of humidity levels in your home. If you have a humidifier on your furnace to keep humidity levels at a comfortably high level when heating, faced duct insulation will ensure that the moisture finds its way to the living spaces of your home rather than being lost through those leaks, holes and seams.
When using central air conditioning, it is important that uncomfortably humid air reach the indoor coil where the moisture can be condensed and drained away. You’ll feel more comfortable at a higher temperature when the air is relatively dry, and this means you can set your thermostat higher.
A final reason to consider duct wrap is that it prevents condensation from forming on ducts when air conditioned air is moving through them. This will prevent dripping from the ducts into living space.
Some of the duct work insulation products on the market meet federal requirements for tax credits for the installation of energy efficient building materials. Check with the manufacturer or your insulation contractor for details on which products are part of the tax credit program.
The basic recommendation from insulation contractors is that you should add one to three inches of insulation to your ductwork. Here are the relative values:
- 1 inch of insulation: R-value of 1.9
- 1.5 inches of insulation: R-value of 3.5
- 2.5 inches of insulation: R-value of 6.0
- 3 inches of insulation: R-value of 8.0
The more extreme climate in which you live – very hot summers or bitterly cold winters – the more insulation you should consider adding for cost-effective energy efficiency in your home. Get estimates from several insulation contractors in your area to determine the best choice for your home at the most competitive prices.
In addition, the longer you plan to live in your current home, the more insulation it makes sense to add. The long-term benefits of adding more insulation are outstanding.
The most common type of duct work insulation is the foil-faced wrap. The facing acts as a moisture barrier to help control indoor humidity n all seasons. The insulation used most often is fiberglass or mineral wool, also known as rock wool. Like fiberglass, mineral/rock wool is produced from spun molten material, in this case molten slag.
The insulating value of duct insulation ranges from R-1.9 to R-8.0.
This duct insulation cost, or HVAC insulation cost, will help you anticipate the cost of the project before you contact insulation contractors in your area.
Table 1: Prices shown for Duct Insulation, divided down into Material per Sq. Foot and Labor per Sq. Foot:
|Insulation Rating||Material per Sq. Foot||Labor per Sq. Foot|
|R-3.5||$0.33 to $0.55||$0.60 to $0.72|
|R-6.0||$0.80 to $1.10||$0.65 to $0.75|
|R-8.0||$.085 to $1.20||$0.65 to $0.80|
For every 1,000 square feet of insulation installed, expect supplementary materials and supplies to cost $25 to $40.
For the best prices on the project for your home, get written estimates from at least three contractors who know that they are competing for the job.
Get Tips from the US Department of Energy on Saving Money with Duct Insulation
Learn about Duct Insulation Options