Footings are typically the first objects to take shape on the site of a new house, and in no time they have been surmounted by foundation walls, buried under yards of backfill, and with any luck are nothing but a distant memory as the house is built on top of them.
Their appearance may be brief, but footings play an important role in the long-term stability of the structure. Footings distribute the weight of the foundation, and in turn the weight of the house, and prevent uneven settling that leads to structural damage. The more problematic the soil, and the heavier the structure, the more important footings become.
For Pioneer Builders in Port Orchard, Washington, footings for a two-story house might be no more complicated than a 15-in.-wide swath of 3000-psi concrete 8 in. thick. A frost line just 12 in. below grade doesn’t hurt. “You scrape the ground and you’re there,” says Pioneer Vice President Bryan Uhler. But if you’re designing a house in parts of Texas, where expansive soils are the norm, footings can become a complicated engineering exercise that adds tens of thousands of dollars and months of planning to the project.
Footings support foundation walls, spreading the weight of the structure evenly on the soil below and preventing foundations and the structures they support from buckling, sinking, or cracking. In many locales, footings are made of steel-reinforced concrete, but the International Residential Code (IRC) also allows footings to be made from crushed stone, and builders lucky enough to be working in parts of the U.S. with predictably stable soils may be able to pour extra-thick foundation walls and skip separate footings altogether.
Soil type is an important consideration
No matter what type of foundation wall the designer chooses—concrete, concrete block, pre-cast concrete, or…