Crawl Space or Slab?


Slab foundation

Crawl space

What is it?A concrete slab foundation is made up of several inches of concrete and reinforcement iron rods, sitting slightly above ground level, also known as “at grade,” where the floor of the structure will sit. A concrete slab is arguably the least expensive foundation to produce and can reduce the cost of building a home by $10,000 or more. Sanitary plumbing lines are placed in the ground before pouring the concrete and remain encased in the floor. Homes built on slabs sit slightly above grade and are ideally suited for dry climates, rocky soil, or, of course, for occupants unable to navigate steps.A crawl-space foundation is an unfinished shallow space beneath the main floor of a home and the ground. The space between is generally 3 to 4 feet. Although it’s similar to a basement in that all mechanical and plumbing work sits beneath the structure, a crawl space is considerably less expensive than a basement, while providing many of the same aesthetic advantages. Homes built on a crawl space sit several feet above grade, giving the appearance that the home is high off the ground. They require adequate ventilation to reduce the effects of condensation and to expel stagnant air.
The way to go if you want to save money.

Advantage: slab

Most experts agree that a crawl space is the better alternative to a traditional basement. The advantages it has over its slightly less expensive cousin make any additional costs well worth it.
AccessBecause slabs encase your sanitary sewer lines in concrete, should you have a major problem with, say, tree-root encroachment, ground shifting, a break in a line, or other major malfunction, you have little choice other than breaking through your finished flooring to make repairs.Perhaps the greatest advantage of a crawl space is the access it provides to your entire plumbing and mechanical infrastructure.

Advantage: crawl space
Heating and cooling ventsSlabs also don’t allow for heating and cooling vents to be placed on the floor.A crawl space gives your first floor the look of a home that has a basement. Placing vents on the floor of the first level of a home is an important aesthetic quality that’s more desirable to many home buyers. In addition, because hot air rises, your home will stay more comfortable in the winter.

Advantage: crawl space

Exterior appearanceSlab homes hug the ground.Homes built on crawl spaces sit comfortably above grade, giving the structure a more stately appearance and a built-in buffer from rain, groundwater, insects, and other pests.

Advantage: crawl space

MaintenanceA slab requires neither ventilation nor upkeep.

Advantage: slab

Crawl spaces must have adequate airflow to reduce moisture buildup, which can lead to a mold problem. Also, crawl spaces require insulation to protect pipes from freezing.
Better choice The WINNER
All in all, the money you save with a slab isn’t worth the added risk. More information: