Building a house starts from its foundation (the most important part). The weight of the house are supported by the footers and foundations, and they are usually made from concrete or masonry. After this is completed, the ground floor can be built from wood or concrete. And when the floor is completed then framing (the process of using wood or metal beams) begins.
Houses today are generally built on a foundation that is either a slab, a crawl space, or a basement. Basements are more expensive to build, but many people are willing to pay for it since land costs are very high because basements allow for the more living space. Depending where and when a house was built, its foundation can be made of brick, stone, preservative-treated lumber, concrete block, or poured concrete. The most common foundation's material today is concrete.
Usually they will also contact the plumber, electrician and heating company to ask them if there is anything they need to install in the foundation before the concrete is being poured.
The bottom part of a foundation is called a footer (or footing). It is usually wider than the foundation wall, footer is located about 12 inches below the frost line (this is the average depth at which soil freezes year after year).
For a crawl space, they will dig a set of trenches and holes before pouring concretes into them so that the interface between the ground and the foundation wall can be created. The width of these concrete beams are controlled by the compressibility of the soil. The floor of our home is built up on foundation piers. It gets our house up off the ground, this type of foundation is very useful in damp or termite-prone areas.
A crawl space allows access aruond the lower level of our home. We can crawl into the access foor below our home to handle most of our maintenance issues. Many times the electrical, HVAC ductwork and plumbing will be housed here also. With this type of foundation, moisture is one of the biggest drawbacks, it can lead to potential termite damage, rotten floor joists, and/or mold.
Remember that a slab foundation also means our first floor, so our house is close to the moist ground below it. If we live in a colder climate then we can also notice that the flooring on top of its hard surface can feel cold and hard.
A basement is a mixture of both. One of the main differences compared to crawl space is the height. Basement usually have high ceiling so that people can walk around whereas crawl spaces mostly range from one to four feet. Other differences is that crawl spaces are uninhabitable.
Water is a foundation's number one enemy. A house can experience movement, therefore water should be kept away from the foundation once the initial drainage is established.