How Does Duct Sealing Work & Is It Worth It?

In the dog days of summer, with the heat and humidity of the outdoors becoming unbearable, we often retreat into our air conditioned homes, ready to escape the heavy summer atmosphere. However, some of us may find the indoors to be a less than ideal escape. With poor ducting and insulation work, the heat of the outside can influence the indoor temperatures, causing frustration and discomfort. 

Duct sealing is the practice of insulating and properly sealing the metal units that carry conditioned air throughout the home. These duct units are normally placed in the walls, crawl space, basement, or attic of a home, and are greatly affected by the drastic sway in temperature from the outside. This means that during the summer, when you’re trying to cool your home, the cold air you’re paying for is traveling through these hot vent ducts--reheating the air before it ever reaches a room! The inverse happens in the winter, and in the end, you’re spending more money for your home to be less comfortable. 

How Duct Sealing Works

Sealing Ducts

The process of Duct Sealing is usually accomplished in one of two ways: Duct Mastic or Spray Foam.


There are a few different ways that contractors can seal your ductwork for maximum productivity. The important part is ensuring that no air can escape, and that the metal tubing is properly ensconced in insulation to combat the wildly varying temperatures that your attic will see each year, as the seasons cycle. 

Typical methods of Duct Sealing include

  • Duct Mastic- Widely regarded as the best solution for Duct Sealing by many professionals in the industry, Duct Mastic is a gooey, non-hardening material, which is non-toxic and flame resistant. Mastic sealant is often applied using a caulking gun, or a putty knife, and can last up to 20 years. 

  • Spray Foam- The method of using spray foam is gaining popularity within the field for various reasons. For one, spray foam is non-toxic and offers a quick application process. A professional will seal off the vents in each room of the home, and hook up the installation machine. Once turned on, the machine pumps an atomized polymer material into the vents, sealing the microscopic gaps and faulty connections. 

What are the Benefits of Duct Sealing? 

Benefits to Duct Sealing

Duct Sealing can help keep your home happier, healthier and with more money in your pocket.


There are many benefits to having your ducts sealed, which include:

  • Improved Indoor Air Quality--Dust, dirt, and musty smelling air from your attic can easily make its way through the small gaps and leaks in your ducts, spreading throughout your home once the air kicks on. Duct sealing helps close any of these gaps, making it nearly impossible for these air pollutants to enter.

  • Money Saving Capabilities--When you seal your air ducts, your conditioned air won’t be leaking out of the ducts before reaching the vents, or losing or gaining heat due to lack of insulation. With proper duct sealing, homeowners on average can save 20% on their energy costs.

  • Improved Longevity of HVAC Systems--Duct sealing helps out the heating and cooling systems, allowing the machine to work less to maintain air temperature. With less air loss and more temperature regularity, you’ll need to spend less time, money and energy on maintaining the heating and cooling systems within your home, which is always a good thing. 

Finding a Qualified Duct Sealing Contractor

When thinking about embarking on a duct sealing project, you’ll want to look into companies that work exclusively in the attic, or specialize in energy saving projects. 

Thankfully, our Attic Systems Network has dealers across the nation who are expertly trained in energy conservation practices and methods. Our dealers offer free, no obligation estimates and consultations so that you know from the beginning just what you’re in for, and how much the project will cost, down to the very last penny. 

If you’ve been experiencing heat or energy loss and think that duct sealing could be the solution for you, reach out today--we’re just a click away