Different Foundations Types

There are several basic types of foundations that are found under homes across the United States. The Pier and Beam and the Slab On Grade are most commonly found in Texas especially in the Dallas, Fort Worth, Houston, Austin and San Antonio areas. Basement foundations are typically found farther north. This article will cover the Slab On Grade and the Pier & Beam Foundations.

Slab On Grade Foundations

This foundation is constructed of concrete and is poured on-grade. Many Slab Foundations use Post-Tensioning Cables to increase the tensile strength of the entire slab.

This process while adding stability to the foundation can also be a problem in some instances. The tension from the cables can cause the slab to “Cup”. Cupping is a condition that occurs when there is some expansion of the soil around the perimeter of the slab. The lifting effect of the expanding soil along with the lifting effect of the post-tension cables can together raise the perimeter leaving the interior areas at the original lower elevation. To the inexperienced it appears that the interior is sinking. Failure to correctly diagnose this problem can lead to costly repairs that do not address the problem and could actually cause more damaged. The diagnosis of this problem is best left to a professional.

Pier & Beam Foundations

The Pier & Beam is sometimes called the “Crawl Space” foundation. This foundation type typically has a perimeter that is made up of solid concrete which supports the exterior walls of the structure. It is sometimes made up of other materials, the most common of which is masonry concrete blocks.

The interior area is elevated and is supported by a number of stringers (beams) that sit on top of piers. The stringers are spaced evenly along the length of the beam. The spacing of the Beams and the Piers is typically on 7 foot centers.

Building Permits

A Building Permit is a document issued by the city inspector's office. It is permission from the city to move forward with modifications to your home. Most cities require a building permit for foundation repair.

Building Codes

The list of minimum allowable requirements for a particular Building Permit is what makes up the Building Codes that are applicable to your project. Some building codes require a minimum allowable height for the Crawl Space. They may also require that all wooden piers be replaced with masonry piers. Different cities may have different building codes.

It is very important that you understand your local building codes and that you or your contractor obtain a Building Permit before starting any repairs. If you do not take this step you could be liable for expensive fines and/or penalties. It is even possible that your entire structure could be subject to demolition if it cannot for some reason meet the minimum building codes.