Price calculator Price Your Job in 60 seconds

Duct Insulation: Everything You Need To Know

March 28, 2022

An HVAC system runs efficiently when every component is in top shape. However, some things about our HVAC systems may still be unknown. For instance, if you have ductwork for heating and cooling in your home, it may require insulation.

Learning more about these matters will help you make better decisions for your home and wallet. As expert HVAC contractors, we’ll share some of our expertise regarding duct insulation. We’ll touch on aspects like the why and how of duct insulation in a comprehensive guide. Read below!

What Is Duct Insulation?

Duct insulation is a material used to prevent heat loss and, in some cases, sound intrusion. A recurrent question is “Can you put insulation around ductwork?” and the answer is yes. Duct insulation can also go inside the ductwork, ideal for soundproofing your ductwork.

Is Duct Insulation Necessary?

While duct insulation isn’t strictly necessary, meaning your system can run without it, it is imperative when you want to improve its overall efficiency. It is known as leaking when the air and temperature transported through your ductwork are lost. Insulation is a barrier that prevents this from happening. It simultaneously results in many benefits:

Does insulating heat ducts help? Absolutely. Nowadays, we constantly try to make heating and cooling systems more energy-efficient. Duct insulation is a simple way to do so. Additionally, if your ducts are noisy, you can opt for sound installation as well.

What Insulation Do You Use For Ductwork?

There are a few material options available for insulating ductwork. We’ll break them down so you can see which one would work best for you. Before that, however, you need to consider the factors that affect the type of HVAC insulation you choose:


Fiberglass is the most common and effective type of duct insulation. It is made of glass turned into tiny fibers attached to an aluminum backing that keeps it together. It also has a coating for moisture resistance (every type of duct insulation must have it). 

Fiberglass comes in different thicknesses, forms (flexible or rigid), and R-values. Fiberglass can work for both the inside and outside of ducts. If you want to use it to insulate the ducts from the inside, it must be secured with perforated aluminum foil.

Fiberglass insulation is an excellent option at a low cost. It has low thermal conductivity. A downside can be that it needs to be inspected for moisture absorption.

Cross-linked polyethylene foam

This type of duct insulation is used more for exposed ducts. They don’t have wrinkles and will look more uniform than other materials. They are also safer to work with, although the upfront cost can be higher.

Rockwool with perforated metal sheet

An excellent duct insulation option for soundproofing is Rockwool. They are secured with perforated metal sheets on the inside, great for large ducts. The second one is more resistant against high wind speeds than fiberglass with perforated aluminum foil and Rockwool.

How Do You Insulate Ductwork?

If you want to install duct insulation, the correct procedure is to first seal the ducts by identifying the leaks (typically around seams), following up with duct sealing tape or duct mastic as needed.

Once your ducts are entirely sealed, the duct insulation material of your choice can be applied. It is always best to recur to professionals for this task.

And there you have it! Don’t forget to add duct insulation if you have current uninsulated ductwork or install a new HVAC system. Stay tuned for our blog for more helpful guides, how-to’s, and advice. If you also want to explore more energy-efficient options, at R&R Mechanical Service Inc., we offer many of those. You can browse our products today!

Find Us

R&R Mechanical Service Inc - Google My Business R&R Mechanical Service Inc - Yellow Bot R&R Mechanical Service Inc - Angies List R&R Mechanical Service Inc - Yelp R&R Mechanical Service Inc - Daikin
Facebook Twitter BBB Instagram HomeAdvisor Elite Service Award - R & R Mechanical Services, Inc.
US Boiler Mitsubishi Logo Nuew Natex Rinnai Utica Bolers
Call Now Button