The Cost of a Basement vs. a Crawl Space Foundation

When you’re building a house, you have to consider the crawl space vs. basement advantages and disadvantages. Your budget may force your decision, but if money isn’t the only consideration, installing a basement or a crawl space may come down to personal preference. Do your research carefully before making a final determination, as your decision is pretty much final. It is, however, possible to lift a house with a crawl space and create a basement, but that’s not an expense most people would take on.

Nationally, the average home foundation costs approximately $8,000, but the range is between $4,000 and $12,000. When it comes to excavation, a basement requires at least 8 feet, while a crawl space is usually between 3-to-4 feet deep. More labor means higher costs.

Expect an unfinished basement to cost between $10-to-$25 per square foot, while a finished basement will run between $30-and-$100 per square foot, as per Home Advisor. Overall, a basement will cost between $18,000-to-$30,000. Those higher costs don’t only concern the poured concrete. A great deal more labor goes into digging a basement, including the grading. You may want to install a good drainage system, which can save you money, in the long run, should the basement take on water. A standard basement only has an entrance from the home’s interior, while a walk-out basement also allows access from the outside.

Expect a crawl space foundation to run about $7 per square foot, according to Home Advisor. Depending on the size of the house, that means a crawl space will cost between $8,000-to-$21,000. Besides the basement and crawl space, another option is the slab foundation, which is the cheapest of all, at approximately $4 per square foot, or $4,500-to-$12,000.

There are pros and cons to crawl spaces and basements, so you must determine if the former outweigh the latter when it comes to your home site. The basic pros and cons of each involve money and maintenance, with crawl spaces costing far less to build and less to maintain than basements. Unless the bottom line is the only factor, examine the advantages and disadvantages of each when making your decision.

On the plus side, there is enough room within the crawl space for the installation of plumbing and HVAC equipment, and you can install additional piping relatively easily. However, since there is little protection in the crawl space, HVAC equipment, especially, may not work as efficiently as it would in a basement setting. While crawl spaces don’t offer the storage capacity of a basement, it is a place where you can store outdoor items. While many people install ventilation around the crawl space, you can also opt to close it off completely.

Since the crawl space does elevate the house, as compared to a slab foundation, it offers some protection from termites. However, larger animals, including rodents, may find the crawl space an ideal place to dwell. A crawl space is also vulnerable to moisture, and that means careful insulation of the floor above the crawl space. In return, your floors will feel warmer. Install a vapor barrier above the soil, sealed at the foundation walls, for moisture control. Vapor barriers aren’t optional in moist climates, so add $1-to-$3 per square foot for this insulation.

Crawl spaces don’t protect the home during a storm. Even with vapor barriers, it’s likely moisture will creep in, creating mold issues. You must check the crawl space regularly to address these problems. One option for combating moisture is the installation of a crawl space humidifier. It’s also necessary to insulate a crawl space’s exterior walls. In the winter, the crawl space can make heating a home somewhat more expensive. However, you aren’t heating the crawl space per se, which is not the case with a basement.

Unlike a basement, a crawl space tends to be relegated to "out of sight, out of mind" for many homeowners. That means when there are moisture or mold problems, you may not realize it until the situation is serious. If you decide to go with a crawl space, make a point of checking it regularly, especially when there has been a lot of rain.

Basements have a far higher return on investment than crawl spaces. A basement offers additional living space, which a crawl space does not. You don’t have to finish your basement at the time of construction if that will strain your finances. You may not yet know exactly how you want to use your basement space, and that may change over your course of time in the home. For example, you may not have children when you build your home, but if they come along later, the basement may make an ideal play space, media center or family room. If you have a lot of friends and family visiting, turn your basement into a spare bedroom. You can finish your basement as time and finances permit. On the other hand, if you don’t have the funds for a basement, or don’t think you’ll need the extra space, you’ll save money by installing a crawl space foundation.

A basement aids in maintaining the foundation’s integrity over time. That’s because basements serve to anchor the property to the ground as they extend the foundation beneath the frost line, according to Indiana-based Reinbrecht Homes and Construction.

Basements are more expensive than crawl spaces, and like them, are prone to moisture issues, including mold formation. Basements may also flood, and many homeowners can expect inches or feet of water in their basement after heavy rains or a hurricane. The basement may flood due to backed up municipal sewer systems, creating a serious health hazard. Whether its water in the basement or worse, you could end up having anything stored there, or your furnishings, ruined.

Your decision may depend on the part of the country in which you live. There’s a reason certain foundations are more often found in a region than others. In cold climates, basements are common, as it is already necessary for the contractor to place the footings below the frost line, deep into the ground. In warmer climates, crawl spaces or slabs are more frequently found. It’s not that you’ll never find crawl spaces in northern climes or basements in the south, but having a foundation out of sync with area preferences may affect your property’s value when you want to sell. That’s especially true in colder areas, where basements are so often used for storage and living space. While you do have to heat a basement, you don’t have to air condition this living space during hot summer months. The natural ventilation of a basement generally keeps it cool even during the most sultry, humid weather.

If you live in an earthquake-prone part of the country, a crawl space is generally preferable. If the ground shifts, that can cause permanent damage to other types of foundations, so crawl spaces are the foundation of choice in an area where soils may slide. Crawl spaces are also preferred in areas prone to flooding and dry climates. If the soils in an area are hard to dig through, it’s likely you’ll find more crawl spaces than basements.