Should I Insulate My Crawl Space | Crawl Space Ninja (2024)

FAQs

Do I really need insulation in my crawl space? ›

Crawl space insulation is just as important as wall insulation. Insulation beneath the floors of your home and along foundation walls can help improve energy efficiency and preserve your home's air quality.

More recent research from building scientists explained that crawl spaces should be sealed, insulated, and outfitted with a vapor barrier to control moisture, improve comfort, and decrease energy use. The process of sealing the crawl space includes using airtight crawl space vent covers to block the vent openings.

This is because dirt floors are a major source of moisture and can lead to a humid, wet crawl space. If this isn't insulated, you may be wasting energy throughout your home. One solution for this is insulating a crawl space with a dirt floor. This will prevent condensation, pest problems, and other issues in your home.

Crawl space encapsulation refers explicitly to adding a heavy-duty moisture barrier to the dirt floor of your crawl space, sealed foundation vents, insulated walls, and special crawl space dehumidifiers.

On the other hand, if your insulation is in good condition and there are no major issues with your crawl space, then there's no need to remove it. As noted above, insulation is beneficial in helping keep your home more energy efficient by preventing heat loss through the floor.

There is really no reason NOT to have a vapor barrier in your crawl space. Some installers will tell you that you only need a vapor barrier in your crawl space if the “floor” of your crawl space is dirt, but the truth is that installing a vapor barrier is a fundamental component in keeping your crawl space dry.

While crawl space encapsulation along with a dehumidifier will make the air in your home cleaner and drier, adding an insulation vapor barrier as well will make your home warmer. You can even heat and air condition your crawl space for added comfort.

Ventilated Crawl Spaces

Experts use fiberglass insulation below the subfloor. The subfloor is the area above the crawl space and below the home. This can be conveniently installed without issue. Ventilated spaces are most suited to utilizing R-15 or R-19 fiberglass insulation, depending on the size of the floor joists.

Crawl space insulation might not be at the forefront of your mind but forgetting about it is an expensive mistake. Uninsulated ducts that run through unconditioned spaces can lose more than 30 percent of their heating or cooling capacity. So you'll save money by insulating them.

Faced insulation is ideal for spaces that have no existing insulation, such as exterior walls, attic ceilings, crawl spaces, and exterior basem*nt walls. Please note that the proper way to install it is to have it installed facing outward or towards the person installing it.

Are homes with crawl spaces colder? ›

Makes Your Home Colder

If your crawl space is vented or has openings to the outside, cold air will flow in unabated. The stack effect causes this cold air to move up into your living area, causing a multitude of problems. Your floors and walls will become noticeably colder during the winter.

Unfortunately there isn't a way to prevent air from entering your crawl space, whether hot or cold. During colder months, drafts of cold air will lower the overall temperature of your house; the natural temperature of a crawl space should be about 50 degrees.

Yes, in most cases.

One exception to this rule is closed-cell spray foam insulation, which does not require an additional vapor barrier due to its moisture-resistant properties. Encapsulating your crawl space in combination with insulation can provide further benefits for your home than insulation alone.

Are there any negatives to crawl space encapsulation? The only downside is that it can be costly since it's a major home renovation. It costs about $5,500 to encapsulate the crawl space of an average American home, but it can go as high as $15,000. Home upkeep costs could also go up due to additional maintenance.

Increased comfort: Underfloor insulation also directly impacts the overall comfort of your home. Insulating your floors keeps them warmer and more comfortable to walk on during the winter, and it helps make your living area cozier and more inviting.

Basem*nt or Crawlspace Wall Insulation:

Zone 3: Add R5 insulative wall sheathing or R13 batt. Zones 4A and 4B: Add R10 insulative wall sheathing or R13 batt. Zones 4C and 5–8: Add R15 insulative wall sheathing or R19 batt.

While crawl space encapsulation along with a dehumidifier will make the air in your home cleaner and drier, adding an insulation vapor barrier as well will make your home warmer. You can even heat and air condition your crawl space for added comfort.

Homeowners often install insulation under the home's floor joists, inside the crawl space, to improve the home's heating and cooling efficiency. Whether the insulation was installed professionally or by the homeowner, fallen insulation is most often not due to improper installation; rather it's a sign of high humidity.