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Crawl Space Cold Getting into Your Home?

Drafty windows and doors aren’t the only things that make your home cold in the winter. The vented and exposed crawl space beneath your home also contributes to colder indoor temperatures.

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If you live in a home with a crawl space long enough, you will start noticing how this low-lying area affects the conditions indoors. A vented or exposed crawl space allows cold air to flow in during winter and lower the overall indoor temperature. Floors, walls, and interior surfaces will get cold, and this cold environment will force you to run your heating system for many hours to warm up your rooms. 

vented crawl space with bad insulation

How Does Cold Air Move? 

Cold air gets into your home and moves through a process known as the stack effect. When this upward-moving air gets into your home, it will cause a myriad of problems. Cold floors aren’t the only reason to have your crawl space encapsulated. The stack effect could also transfer dust mite feces, mold and mildew, and nasty odors making the air you breathe unhealthy for your family’s living space. 

Just as it’s crucial to prevent moisture from getting into the crawl space, it’s equally important to control unwanted cold air from causing energy loss. Many homeowners tend to replace drafty doors and windows or insulate walls without thinking about their crawl spaces. But sealing and conditioning this space can make your home energy efficient. Let’s look at ways you can control crawl space temperature and maintain favorable conditions for months to come. 

Insulate the Crawl Space 

In cold climates like Columbus, OH, rigid board insulation can be applied on the crawl space walls. We do encourage you to use a two-part spray insulation on the underside of the subfloor in the rim joists. 

Instead of insulating rim joists alone, insulate the perimeter of the crawl space with foam board insulation. It’s much more energy-efficient to insulate the surrounding area. With the foam board in place, the entire crawl space can regulate and maintain the ideal air temperatures. Your crawl space won’t get too hot or too cold. 

While you’re at it, don’t forget to insulate the access door. This door acts like any door that goes to the outside, and it needs to be airtight. It’s also a good idea to weatherstrip the edges of your entry doors to keep draft out. Since no cold air passes through, your crawl space will maintain a better climate just like the rest of your home. 

Thermal crawl space insulation prevents heat loss, meaning the crawl space will be noticeably warmer, just like the rooms above. As a result, you won’t have to heat this area, so you won’t be spending lots of money heating your home in winter and cooling your home in summer. 

Seal the Crawl Space 

Start by encapsulating the crawl space area. This entails covering the dirt floor and walls with a thick 20-mil plastic vapor barrier. The polyethylene material goes over obstacles and beams then sealed at the seams with a special tape. Gaps that exist along rim joists are carefully sealed. 

Prior to this, the contractor will seal vents with airtight vent covers. Your sealed crawl space now becomes a part of the conditioned area of your home. Temperatures won’t fluctuate and your home will stay warm and dry during winter. Best of all, heat loss won’t happen nor will pipes freeze. 

Seal and Insulate Ducts 

If your home has air ducts and plumbing that runs between joists, seal and insulate them. Ducts mostly connect to the outdoors above your house. So, it’s crucial that they don’t have leaks or holes. A leaky or punctured duct can cause unwanted air from the crawl space to move up into your home and air from your home to escape into the crawl space. You can seal holes easily using mastic tape. Duct tape also works, and it’s long-lasting. When sealing ducts, make sure you inspect connection points on the floor and walls. 

Once you seal the leaks, wrap the ducts with protective foil. This material will discourage mold and condensation from forming. The extra layer of insulation will also enhance your energy as it prevents ducts from losing heat. 

Use a Dehumidifier to Control Humidity 

Insulating your crawl space floors isn’t a direct ticket to a warm, dry, and comfortable home. You still have to address the issue of crawl space moisture. Insulation won’t totally control humidity in your crawl space. Left unchecked, the excess moisture can cause wood rot and mold. We encourage you to go for an energy-efficient dehumidifier with an air filter. Once it’s set up, a thermostat will trigger the machine to dry out the air. 

Be sure to contact the crawl space specialists at Ohio Basement Authority for a free crawl space repair quote when you’re ready to seal and insulate your crawl space. We have encapsulated hundreds of crawl spaces and use patented products to deliver successful projects and healthier homes.

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1270 Hillsmith Dr.
Cincinnati, OH 45215

Columbus Office
2421 McGaw Rd.
Obetz, OH 43207