Dallas Foundation Repair - Different Types of Concrete Foundation

There are three basic types of foundations in use today in the construction of a home.

Slab Foundations

A slab foundation is a foundation built without delay on the soil with no basement or crawl space. Slab foundations are common in areas where soil conditions are not acceptable for a basement, and are the most typical foundation found in warmer areas like Florida, Arizona, California and Texas, or anywhere where the depth between the soil and stable underlying rock is awfully shallow. They consist of a concrete slab that is typically 6 to 8 inches thick. Embedded within the slab is a grid of supporting ribbed metal rods known as "rebar." Even in locations where basements are prevalent, slab foundations are typically laid to serve as the base for structures like garages, pole barns, and outbuildings. Slabs have the disadvantage of being difficult and expensive to repair when they settle and crack, and plumbing lines that stick out from the soil upward thru the concrete may also be pricey to repair. In areas where the underlying soil is thick or prone to over the top growth and contraction, cables are embedded which can be tightened to provide better horizontal support and minimize the width of cracks.

Crawl Space (Pier and Beam) Foundations

A pier and beam foundation includes either vertical wood or concrete columns (piers) that support beams or floor rafters above the ground. The areas between the soil and the base of the house floor is regarded as the crawl space. These foundations are built either at ground zero or over a shallow excavation that varies in depth, but is often about 36 to forty inches deep. Less expensive versions have no load-bearing perimeter walls, piers with shallow footings, and no moisture barrier at all over the soil. Crawl spaces that enclosed by a wall or by skirting must have vents on each side to allow air to circulate and help keep the soil dry under the home. These vents must be configured to prevent the entry of rodents and snakes. The first blessings of crawl space foundations are that plumbing lines are readily accessible for repairs, and foundation settlement problems are simpler and less expensive to correct than with slab foundations. A primary disadvantage happens when these foundations are not properly maintained or are created without adequate ventilation, allowing water or pests to cause damage. Crawl space foundations without sufficient insulation applied to the base of the house floor can be terribly energy ineffective in a cold climate.

Basement Foundations

This foundation provides living space below the home, below the ground elevation. It is largely a slab foundation with walls and a floor. Basements are most frequently built in cold weather climates like the Northeast, Midwest and Rocky Mountains, and in places where the cost of excavation is not prohibitive. The floor and walls are built, then the house itself is built over that. Basement foundations have the advantage of providing useful space for uses, mechanicals systems, and storage not available in the prior 2 kinds of foundations. The primary disadvantage of basements is that because they are often below ground level, they are vulnerable to leakage, mold formation, and flooding. Basements in wet climates must always have a working drain and pump in the floor to combat flooding.