Before we take a deep dive into the types of insulation that can be used for crawl spaces, let us take a look at the ideal characteristics you should look out for in insulation material:
- R-Rating: A high per-inch R-rating ensures the insulation remains effective for longer periods and does not wear out easily.
- Ease of Installation: Easy to install insulation that does not create a mess is always advisable.
- Budget: The material that provides the best value for money is naturally more preferable over its counterparts.
- Resistance to moisture: The insulation should be resistant to moisture and humidity and should not be damaged easily.
- Mold and microbial growth resistance: The insulation material should have a high resistance for mold and microbial growth as the presence of these pathogens on the material could significantly impact their effectiveness.
- Flexibility: The insulation should be easy to install around obstacles and utilities.
- Compactness: Insulation material should tightly adhere to the wall and should not allow spaces or gaps to exist.
Types of insulation:
Fiberglass: Manufactured from fine glass fibers, this insulation is usually yellow, pink, white, or gray in color. Fiberglass is easy to install and readily available in the market. However, its low resistance to moisture, mold and microbial growth in addition to its ineffective insulation properties makes it a secondary choice to rigid foam.
Closed-Cell Spray Foam: The insulation material is stored under pressure and expands to form foam when sprayed. The nature in which it is stored makes its installation fast and effective. In addition to its hassle-free installation, the closed-cell spray foam can be easily installed around objects, has a high R-value per-inch, automatically moves into spaces to fill gaps and voids, and is highly moisture resistant and creates a vapor barrier. HOWEVER, the insulation material is expensive and permanent in nature. If you were every to experience a water leak or moisture damage, the repairs could be 3-4X expensive due to the difficulty to remove spray foam.
Open-Cell Spray Foam: It has all the properties of cold-cell spray foam except its moisture resistance and vapor barrier nature. This means that the open-cell spray foam is an expensive insulation option minus the high R-value per inch and the moisture resistance provided by closed-cell spray foam. Spray foam insulation can make future unexpected structural repairs incredibly difficult so it’s not ideal in homes that could have leaks or termite damage.
Rigid Foam: Foam boards are cut out of rigid foam and are mounted on crawl space walls. Its solid nature makes installation around obstacles a bit difficult. Rigid foam boards offer a variety of benefits such as moisture resistance, vapor barrier protection, easy installation, high R-value per inch, longevity, and affordability. By insulating the walls, the entire crawl space is warmer, offering the best results of any crawl space insulation.
Rigid foam boards are the most preferred insulation material.