A foundation wall is a wall which rests on the footers of the foundation, and provides support for the weight of a house. Foundation walls are a critical part of the construction of a home with a perimeter foundation design, and they are one of the areas of construction in which it most definitely pays to take the time to do the job right. Problems with the foundation wall will ultimately lead to problems with the house, up to and including complete structural failure.
A number of materials can be used to make a foundation wall. Poured concrete is a common and popular choice, with some contractors using modular walls which are actually poured off site and transported to a building site. Blocks, bricks, and stone can also be used. In all cases, the materials must be load bearing, and the wall needs to be designed and built so that the weight will be distributed evenly over the footers of the house.
One of the most common problems with foundation walls is cracking. Foundation cracks can be benign or serious, depending on the location of the crack, the size, and the direction of the crack. Cracks can appear because the wall was built in a hurry, backfilled before the concrete had a chance to cure, or not properly reinforced. Earthquakes and settling of the underlying ground can also result in cracking of the foundation, as can damage caused by impact to the foundation.
Foundation walls can be installed after a house is built, as seen when a house with a post and pier foundation is retrofitted to install a perimeter foundation. Likewise, damaged foundations can also be replaced. In both cases, the house is usually raised on jacks which support the weight of the house while the foundation work is done. Foundation stabilization can be tricky work, and in urban areas, there are usually entire contracting firms dedicated specifically to repairing, stabilizing, and reinforcing foundations.
For commercial structures, building foundation walls can become much more complicated. The walls must be much larger, much more heavily reinforced, and capable of bearing huge amounts of weight once the building is finished. Engineering firms are usually consulted to design the foundation wall and determine the load requirements, ensuring that the wall will ideally exceed the need, as replacing foundations as a result of a foundation wall failure on large structures is not an enjoyable or cheap process.