Basement Insulation Comparison

fiberglass insulation being installed in a home

How Many Inches Of Insulation Do You Need On Your Walls?

That depends on the type of insulation you're using! For example:

Insulation Type R-Value Per Inch
Fiberglass 3.33
Open-Cell 3.7
Closed-Cell 6
Rigid Foam 4.5

There are several types of insulation available for homeowners wishing to finish their basement or upgrade it for enhanced energy efficiency.

Each type will have its own strengths and weaknesses and should be evaluated so you can choose the one that best suits your priorities and fits the unique situation in your basement.

Traits Of Effective Basement Insulation

  • High R-Rating Per Inch
  • Installs Quickly & Easily
  • Provides The Best Value For Your Money
  • Does Not Support Mold/Mildew Growth
  • Will Not Be Damaged By Moisture/Water
  • Creates Vapor Barrier On Basement Walls
  • Can Be Installed Around Obstacles
  • Can Be Used To Fill Voids

For example, if basement flooding or moisture is a concern, you'll want to be especially sure to choose closed-cell spray foam or rigid foam, since neither insulation type will be damaged by water or support mold growth.

If you're hoping to air seal your home, then spray foam will likely be at least one piece of your solution.

free quote for our professionals to insulate your basement walls and make them ready for finishing.

We can help you choose the best way to insulate your basement and improve its energy efficiency! To schedule your free basement insulation quote with your local Basement Systems Dealer, contact us by phone or e-mail today!

Comparing Different Insulation Types

The insulation you use should be customized to the job called for. For example, blown fiberglass insulation, which is a great idea for insulating an attic, should not be considered at all in a basement environment. Likewise, fiberglass batt insulation is a bad idea for insulating an attic, which requires a very thick layer of insulation (at least 16 inches).

Below, we outline the advantages about disadvantages of four types of basement insulation:

Fiberglass insulation installed in a basement that is being remodeled.

Fiberglass Insulation

Fiberglass insulation is made from extremely fine fibers of glass. This is often installed in the form of "batts" on a basement wall, with insulation that has a cottonlike texture and is pink or yellow in color. This insulation is attached by adhesives to tall rectangular strips of paper.

Advantages:

  • Fiberglass is readily available
  • Inexpensive
  • Can be removed & replaced

Disadvantages:

  • Soaks up water and humidity like a sponge
  • Low R-value per inch
  • Can support mold and mildew growth

Fiberglass Insulation In Depth

Fiberglass is an inexpensive insulation material that's popular among "do-it-yourselfers" for insulating wall studs before finishing the basement. It's readily available at most hardware stores and box stores, and its lightweight, removable design makes it a popular choice.

While fiberglass insulation is excellent in above-grade spaces, it's a notoriously poor choice for basement insulation. Fiberglass can become saturated with moisture from basement flooding, water leaking through walls, and even from water vapor passing through the pores of concrete. Wet fiberglass loses much of its insular value, and as it becomes weighted down it sags, leaving gaps in the insulation at the top. Over time, wet fiberglass will support mold and mildew growth.


Open cell spray foam insulation installed to finish a basement.

Open-Cell Spray Foam Insulation

This insulation forms an expanding foam as it's sprayed. Open-cell foam insulates but cannot seal out moisture.

Advantages:

  • Fast installation
  • Can be used around obstacles
  • Foam expands to fill gaps

Disadvantages:

  • Restrictively high cost
  • Does not create vapor barrier
  • Permanent installation - cannot easily be removed
  • Low R-value per inch
  • Potential for "overspray" and messy cleanup
  • Final thickness of insulation is inconsistent/uneven

Open-Cell Spray Foam In Depth

Open-cell spray foam is also used for air-sealing and insulating, but it's not a good choice for basement applications. Closed-cell spray foam has a higher insulation value: about R-6 per in. compared to R-3.7 per in. for open-cell spray foam.

Also, open-cell spray foam doesn't form a moisture barrier like closed-cell foam does, so it can't seal out moisture --a valuable quality in basement and crawl space areas.


Closed cell spray foam insulation being installed in a basement

Closed-Cell Spray Foam Insulation

This insulation forms an expanding foam when sprayed. Closed-cell spray foam creates a vapor barrier as applied.

Advantages:

  • Fast installation
  • High R-value per inch
  • Can be used around obstacles
  • Foam expands to fill gaps
  • Creates a vapor barrier & resists water damage

Disadvantages:

  • Restrictively high cost
  • Permanent installation - cannot easily be removed
  • Potential for "overspray" and messy cleanup
  • Final thickness of insulation is inconsistent/uneven

Closed-Cell Spray Foam In Depth

Closed-cell spray foam is often used to air-seal the basement's rim joist and other leaks that waste energy. The rim joist (aka band joist) extends around the perimeter of the house, typically resting on the mud sill or directly on top of the foundation.

Knot holes, cracks and gaps above and below the rim joist create many pathways for air to leak into a basement, but these leaks can be sealed effectively with closed-cell spray foam.

In this application, the foam's most important function is air sealing rather than insulating. This sealing work is also useful for all the holes, cracks and gaps that allow basement air to leak through the floor structure and into the living space above.

Closed-cell spray foam comes in two forms. Pressurized cans of "one-part" spray foam are available at hardware stores and home centers. But insulation contractors often use "two-part" spray foam that combines two compounds at an application nozzle.


Studded insulated basement panels for prefinished concrete walls

Rigid Foam Panel Insulation

Rigid foam panels are made with foam insulation that has been shaped into stiff wall panels that are mounted on your walls or between studs. These panels typically use a closed-cell insulation design.

  • High R-value per inch
  • Creates a vapor barrier & resists water damage
  • Can be designed with pre-installed wall studs
  • Can be removed & replaced
  • Lower cost
  • No messy installation

Disadvantages:

  • Most difficult to install around obstacles
  • Cannot be used to fill voids

Rigid Foam Panel Insulation In Depth

Rigid foam panels are lightweight and easy to install. Channels can be cut by the installer to accommodate pipes, wires, and similar obstacles, while the panels can also be customized to work around more significant obstructions.

Rigid foam insulation is often combined with sections of more expensive, closed-cell spray foam, which seals small cavities and areas where it would be difficult for rigid foam paneling to be properly installed.

Rigid foam panels will create a vapor barrier on your basement walls that will keep back water, water vapor, and humidity that could otherwise build in the basement and contribute to humidity levels and, subsequently, mold.

Insulated basement wall panels with metal studs.

Basement To Beautiful Panels™

Our certified dealers can professionally install our Basement To Beautiful Insulated Panels in your home.

These innovative panels combine our advanced graphite particle infused polystyrene foam insulation (rigid foam panels with graphite) with a durable metal stud system.

Once installed, your basement walls will be prepared for finishing, with an industry-leading R-13 insulation rating.

More on Basement To Beautiful Panels

Insulate The Floor Joist Instead?

In lieu of insulating the basement, many homeowners instead opt to insulate the floor joists on the basement ceiling with fiberglass batts.

This has the advantage of providing some energy savings, while the fiberglass batts also provide sound-dampening, allowing for a quieter walk across on the floor above the basement.

However, while the living space of your house is insulated, the basement is not. The space is filled with air ducts and hot water pipes that are best kept hot -- as well as your furnace and water heater.

These utilities will have to work extra hard just to do their daily job. As they work hard, you pay more.

How much can you save by insulating your basement walls? Here's what the USDOE has to say:

US Cities At R-10 Insulation At R-20 Insulation
Buffalo, NY $350 $390
Denver, CO $310 $360
Minneapolis, MN $400 $450
Seattle, WA $280 $320
St. Louis, MO $250 $290
Washington, DC $250 $280

We Insulate Basement Walls!

Our basement experts can help you insulate your walls for added comfort, value, and energy savings in your home. Our basement insulation products will get your basement ready for finishing and help you save hundreds of dollars on your utility bills.

To learn more about how we can help you, contact us today to schedule a a free, no-obligation basement insulation quote! The free quote you receive will include an on-site professional inspection and consultation, as well as a written quote on the cost of any work you'd like done. Before your free quote, we'll also send a complimentary copy of our full-color basement book, filled with information about basement repair and improvement, as well as how our products will help you.

We have locally owned and operated Basement Systems Dealers serving throughout Canada, the United States, and the United Kingdom. We look forward to hearing from you!