When describing foundations all a person has to do it look at nature. How does a horse stand? How can a tree withstand wind? Why don't cliffs over looking the ocean break off and fall in? Part of the answer to every one of these questions is another question. What part of each of these natural items touches the ground?

In the case of living organisms, which are largely mobile, it how the structure of the legs and feet interact with the earth's surface. In the case of a home or building it is how the foundation interacts with the ground.

When properly engineered foundations are the “feet and legs” that enable buildings to withstand the powerful forces of nature. These forces, of course, include gravity, soil expansion, frost heaving, and pressure from water build-up. But even these are just a part of what a competent foundation system has to deal with when supporting a structure.

Excavation and Drainage:

A lot given the go-ahead for development usually has been checked for type of soil and water retention. Ideally, water is repelled and drained away from any foundation so some clay is desirable. Conversely, soil that is too high in clay will cause shifting and buckling. A good idea is to get a soil analysis first then a reliable excavating company who does residential work.

After excavation the ground is leveled off and foundation gravel is placed down first. Then a drain tile is installed off the outside of the area where the footings will be poured to attract water from the footings and walls to drain it off away from the foundation.

Footings:

As the name implies these are the “feet” which transfers the load of the building area to the ground. All footings have to be on solid, immovable ground because the whole structure depends on it. Footings are usually steel-reinforced concrete poured or placed on-site in various shapes and sizes. They are generally a minimum of two to three times wider than the width of the foundation wall. The factors determining the thickness of the footer depend on the combination of the weight of the structure above and the strength of the soil below the footer. For example, 10” - 12" footer will be stronger than a thinner 6” - 8" footer. Forms are usually put down with steel rebar placed horizontally – to assist the footing integrity – and vertically to tie the foundation to the footing.

Foundation:

This is when the building begins to take shape. The foundation is constructed on top of the footer using forms which hold the steel rebar and cement intact until the cement dries. They are basically load-bearing vertical beams which perform a similar function as the structural steel I-beams in large buildings. In essence, depending on the use and soil conditions, foundations can be constructed from a variety of materials: concrete, stone, concrete block, wood, steel, etc. However, this depends on the requirements of the building inspection office in the the area.

Waterproofing:

In many areas waterproofing is required. This is because concrete can act like a sponge for water, especially where there are cracks or in joints. Tar or some synthetic brush or spray-on waterproofing is common but in wetter areas contractors some time use a membrane that has an adhesive backing. This “skin” is wrapped around the whole foundation and down past the footing joint.

Planning Your Home:

In any build, as in many areas of everyday life, the foundation is the most important important aspect. Make sure you get a Renovation Experts professional to do the work for you.