What Is a Crawl Space?: A Common Foundation Type in the U.S.

Almost 15% of homes in the U.S. have crawl space foundations. The reason why is simple. A crawl space is much cheaper to build than a full basement.

However, its low cost doesn’t make it easier and less time-consuming to construct.

Here, we’ll discuss all the necessary details about crawl space foundations.

The name for these substructure areas comes from how they can be accessed. Unlike a basement, you can’t stand in a crawl space or make it into a living space. Nevertheless, you can still use them as storage space if you need one. Even if they seem like a cheaper, less effective solution for some homeowners, crawl spaces have numerous benefits just like basements and slab foundations. For example, they offer lots of space for electric panels and utility lines.

If you have a vented crawl space, you should check whether it meets building code requirements in Michigan. According to regulations, every home with crawl space vents in the state needs to have 500 square feet of crawl space area. However, the rules are different if you have a thick vapor barrier covering the ground of your crawl space. Aside from that, the building code requires that the space between the joists and the ground needs to have outside ventilation.

Regulations also require homeowners to install Class I vapor barriers on the ground and up the vertical wall a minimum of six inches in unvented crawl spaces. Furthermore, it’s essential to make sure that this area has a conditioned air supply. The code recognizes several mechanical drying methods such as permanent dehumidifiers, air from an HVAC system, exhaust fans, or conditioned air from the living space above.

Essentially, crawl spaces are constructed in a similar way as basements. The construction crew will first dig out a space for the foundation and then they will pour the footing. Afterward, they will construct the foundation walls and the rest of the home on top of it.

Crawl spaces are pretty much empty aside from electric wires and other utilities that run through them. But this doesn’t have to be the case if you want to insulate yours and turn it into storage space. However, many homeowners decide to skip on the potential storage space and leave the ground beneath the crawl space empty because it’s much cheaper than pouring concrete.

Just like any other man-made structure, a crawl space will have its downsides. Here are some of these cons that any homeowner should be aware of:

• Poor energy efficiency: During winter, an open crawl space will lower the energy efficiency of your home. The best way to deal with this problem is to cover open vents and encapsulate and insulate the area to lower your heating bills.
• Pest infestation: Crawl spaces are usually dark and humid areas, making them a perfect place for rodents and other pests to gather. If they do end up in there, pests will nest, breed, and live carefree. Unfortunately, they can damage your structure along the way.
• Moisture problems: Crawl spaces are prone to moisture. Air goes through them freely, making the interior humid. This can, in turn, lead to rot, mold, and numerous other problems.