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Fix Your Nasty, Energy-Wasting Crawl Space CleanSpace crawl space encapsulation is the solution you need.

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Comparing Options For Crawl Space Insulation

rigid foam insulation installed on crawl space walls

SilverGlo™ Insulation

At Basement Systems, our experts insulate crawl space walls with our innovative SilverGlo™ Insulation.

This highly efficient insulation product provides a built-in radiant heat barrier and vapor barrier.

The insulation is waterproof, while its reflective surface maximizes the effectiveness of available lighting.

More on SilverGlo™ Crawl Space Insulation

As energy prices continue to soar, homeowners are looking more than ever for ways to conserve energy in their home. By sealing and insulating a home properly, homeowners may save hundreds of dollars or more on their annual utility bills!

As the search continues, many homeowners are looking towards one of the obvious culprits: vented crawl spaces.

Crawl space vents are entryway points for cold winter air, as well as summer humidity -- both of which can place an unnecessary burden on your home's utilities. By sealing and insulating your crawl space, you can eliminate this drain on your utilities, saving you significantly on your energy bills.

What To Look For In Crawl Space Insulation

  • High Per-Inch R-Rating
  • Fast Installation With Minimal Mess
  • Provides The Best Value For Your Money
  • Waterproof/Will Not Be Damaged By Humidity
  • Does Not Support Mold/Microbial Growth
  • Provides A Vapor Barrier As It Insulates
  • Can Be Installed Around Obstacles & Utilities
  • Can Expand To Fill Gaps And Voids
Schedule A FREE Estimate

We can seal and insulate your crawl space quickly! Our crews can typically complete a complete installation of a warrantied crawl space system in less than a day.

To schedule a free crawl space insulation estimate with your local Basement Systems Dealer, contact us by phone or e-mail today! Your free estimate includes a professional inspection, on-site consultation, and customized cost estimate.

Comparing Different Types Of Crawl Space Insulation

There are four basic types of crawl space insulation. Understanding the advantages and limitations of each type will help you to come up with the best energy upgrade strategy for your crawl space.

What follows is how the four common types of crawl space insulation measure up:

fiberglass insulation for a crawl space floor joist

Fiberglass Batt Insulation

Fiberglass insulation is created from very fine fibers of glass, and is typically pink or yellow in color. This is the oldest type of crawl space insulation, and is typically installed between the floor joists of the crawl space "ceiling". is made from extremely fine fibers of glass.


  • Fiberglass is readily available
  • Inexpensive
  • Easy Installation


  • Is ruined by exposure to moisture & humidity
  • Low R-value per inch
  • Can support mold and mildew growth

Fiberglass Insulation In Depth

The strategy of insulating the crawl space by installing fiberglass batts between the floor joists is ineffective for a number of reasons. First of all, batt insulation does nothing to halt air movement. This means that crawl space air that's either too hot or too cold can easily pass through the insulation, making its way into the living space above through cracks, gaps, and holes in the floor assembly.

Additionally, fiberglass batts compress easily, absorb moisture, and tend to fall out from between joists. When this happens, the value of the insulation is lost, and the crawl space becomes a messy, unpleasant area that's likely to support mold growth.

See our Gallery Of Bad Crawl Space Fiberglass Installations

closed cell spray foam insulation insulating the sill plate in a crawl space

Closed-Cell Spray Foam Insulation

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


  • Fast, effective installation
  • High R-value per inch
  • Can be used around obstacles; expands to fill gaps
  • Creates a vapor barrier on surfaces
  • Not damaged by water & moisture


  • 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

Whether applied from disposable cans or large containers, closed-cell spray foam is valued for its ability to stop air leakage, while also providing high insulating value.

Because it expands to fill gaps and cracks, spray foam is best used to air-seal and insulate the rim joist that extends around the house at the top of the foundation. This is where most energy-wasting air leakage takes place in a crawl space or basement.

Closed-cell spray foam can eliminate this threat to comfort and energy efficiency. Another advantage with spray foam is that it stays in place; it won't move, compress or lose its insulation value like fiberglass batts.

Closed-Cell Spray Foam Is Available In Two Forms:

"One-Part" Spray Foam: Pressurized cans are available at hardware stores and home centers.

"Two-Part" Spray Foam: Most often used by insulation contractors -- combines two compounds at an application nozzle.

open cell spray foam insulation installed in a crawl space environment

Open-Cell Spray Foam Insulation

This insulation forms an expanding foam as it's sprayed. Open-cell foam does not seal out moisture.


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


  • 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

Because open-cell spray foam does not create a vapor barrier as it's installed, it is inappropriate for use in a crawl space environment.

Closed-cell spray foam has a higher insulation value: about R-6 per in., as compared to R-3.7 per in. that open-cell spray foam provides.

Foam insulation installed on crawl space walls

Rigid Foam Insulation

Rigid foam panels are created by shaping rigid foam insulation into stuff panels that are mounted on the woos of a crawl space. These panels typically (and ideally) use a closed-cell insulation design.

  • High R-value per inch
  • Creates a vapor barrier
  • Waterproof -- Resists water damage
  • Lower cost
  • No messy installation


  • Most difficult to install around obstacles
  • Cannot expand to fill voids

Rigid Foam Panel Insulation In Depth

Like spray foam, rigid foam insulation offers higher R-value per inch than you get with fiberglass batts. It's also waterproof, stable (it won't compress) and able to stop air leakage when joints between rigid foam panels are taped.

Rigid foam insulation is the ideal material for insulating crawl space and basement walls. Performing this energy-saving upgrade eliminates the need for fiberglass insulation, and is typically part of the crawl space sealing (aka encapsulation) process.

Installation of rigid foam panels is often combined with sections of more expensive, closed-cell spray foam. The panels cover the walls, while the spray foam seals small cavities and areas where it would be difficult for rigid foam paneling to be properly installed.

When installed correctly, 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.

an insulated crawl space floor

TerraBlock™ Floor Insulation

TerraBlock™ Insulation is made with 3/4" expanded polystyrene (EPS) foam insulation.

This insulation is specifically designed to provide a durable layer of insulation on your crawl space floor, while also providing a vapor barrier to hold back moisture.

More on TerraBlock™ Insulation

Insulate The Floor Joist Instead?

Instead of insulating the crawl space at the walls and floors, many homeowners will instead opt to install fiberglass batt insulation on the crawl space "ceiling".

Insulating from the floor joist provides some energy savings by preventing some of the cold from the crawl space from permeating into the rest of the home. This insulation has the added advantage of providing sound-dampening properties, so that there is less noise upstairs as residents walk on the floor located over the crawl space.

While insulating the floor joists will protect your living area, your crawl space will remain as cold as ever during the winter months.

This becomes relevant to the homeowner as the utilities stored in the crawl space, including the water heater, hot water pipes, furnace, and air ducts are cooled in the unconditioned environment.

Locating these utilities in a cold environment will force them to work harder than ever -- which will cost you much more on your utility bills.

Instead, we recommend that you insulate the crawl space from the walls and floors -- protecting the entire space from the cold in the environment.

We Install Waterproof Crawl Space Insulation!

At Basement Systems, our Certified Dealers provide insulation products that are custom-designed for the crawl space. They seal as they insulate, are fully waterproof, and are versatile enough to be installed around obstacles in a potentially low-ceiling crawl space.

You'll love what our products will do for your home's energy efficiency! To schedule a free, no-obligation crawl space insulation estimate with your local expert, contact us by phone or e-mail today!

Our on-site inspection and consultation includes a measurement of your crawl space, an identification of any problems in the space, and a meeting with our expert, who will answer any questions that you have about your crawl space.

Your expert will make recommendations on options that would best work for your home, and the two of you will work together to create the ideal, customized system for your home. By the end of the visit, we'll have a cost estimate, available in writing, that reflects the system you designed.

As an added courtesy, we like to mail along a copy of our full-color crawl space book, Crawl Space Science, which should arrive before our scheduled visit. This book is packed with details about crawl space issues, repairs, and upgrades of all types, as well as details about our products and services.

We invite you to look through this book to get an overview of what we're all about, and to prepare some questions for our experts!

Looking for a price? Get a no cost, no obligation free estimate.

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Quality, Innovation, Patents, Awards

Our innovative and forward-thinking approach to designing products has solved wet basement problems that the basement waterproofing and crawl space industry has faced for decades, and our patented sump pump systems are the smartest and most reliable. Plus we listen to our customers and respond accordingly! Basement Systems Inc. has been awarded 24 Patents and 19 Innovation Prizes on waterproofing products we use every day, including a battery back up sump pump system. This approach ensures the best waterproofing systems and solutions available.