Get Your Daily Entertainment News

How to Insulate HVAC Ductworks and What are the Types of Duct Insulations

Exposed ductworks are more energy inefficient and have air leaks. A poorly sealed duct wasted up to nearly 30% of the heat or cold air in the outer atmosphere. If the insulation on your house’s HVAC ductwork has some leaks or damage, it’s better to replace or upgrade the ductworks to improve energy efficiency and reduce your electricity bills.

Insulating a HVAC Ductwork:

When insulating a HVAC ductwork, use a foil, faced fiberglass insulation with a higher R-value. The metallic foil duct tape is highly recommended by the insulation manufacturer to seal and hold the insulation in one place.

Make sure the foil surface of the insulation is free from dust before you start applying the tape. Peel the paper back off the tape as you apply it to prevent the tape from sticking to itself.

If the existing duct insulation is in a fair condition, it is better to use an additional layer of duct insulation over it. Perhaps, if the insulation is old you should consider the replacement with the new one.

Cut the insulation to the required width and length using the insulation cutting machine. There are many insulation machine for sale in the online store which helps in producing better-quality products.

Apply several smaller pieces of tape across the insulation seam in order to hold it in one place. Seal the entire length of the seam by using a long strip of tape.

Where the section of insulation joints together, use tape all around the joints by sliding the tape under the duct. Peel off the backing paper when the tape is in the correct position.

Make sure that there are no gaps in the main trunk line, and carefully cut and fit the insulation together where the branch lines and registers come together to the main line.

Check every seam and joint in the foil facing on the HVAC ductwork insulation is sealed properly using the tape. This helps in preventing the outside air from penetrating the insulation and condensing on the ductwork.

Types of Duct Insulations:

The following are the types of duct insulations that are commonly used in HVAC systems. The specifications of these insulations may vary for the external and internal duct applications.

Fiberglass Insulation with Aluminum Foil:

The most common insulation material for HVAC systems is fiberglass. Flexible ducts are insulated by using fiberglass material. Fiberglass insulations are having a layer of shiny aluminum foil on the outer surface in order to hold the fiberglass material together. The thickness of the insulation depends on the temperature difference between the air moving inside the duct and the air which is surrounding the outside of the duct.

Cross-Linked Polyethylene Insulation Foam:

Polyethylene is used to insulate the air condition ducts like exhaust ventilation ducts. This type of insulation is a little bit costlier than fiberglass insulations and the concealed ducts are not insulated with polyethylene foam. These types of insulations are more appealing and safer to work with when compared to fiberglass insulations.


From the above, you can clearly see the types of duct insulation and steps to insulate the HVAC ductworks. Make sure your ductworks are having no leaks and cover the ducts by using the different insulation tapes.

Read Relevant Posts Here:

What are the Benefits of HVAC Maintenance

How to Install HVAC System

How to Install HVAC Ductwork

What are the Factors to Consider When Choosing a HVAC System

What are the Types of Ducts