Foundations may not be the most interesting thing to talk about, but it is an essential part of the home-building process. All the other parts of your home depend on the foundation, literally. While the type of foundation you get depends on your budget, house plans, and what part of the country you live in, there are five main types of foundations used in North America today.
A slab foundation is the most basic foundation and is frequently the foundation of choice in warmer climates. It is, as the name implies, a slab of concrete typically six to eight inches thick. The mechanical systems are embedded in the slab and stubbed out for other subcontractors to access easily.
2. Frost-Protected Shallow Foundation
This type of foundation, often referred to as FPSF, is used in northern climates where a traditional slab foundation would be disrupted by frost freeze ground upheaval due to extreme weather conditions. An FPSF is a variation of the slab that has an insulated perimeter dug to depths below the frost line, which could be as deep as 60 inches. The mechanical systems are embedded in the center slab as well.
A crawl, or crawlspace foundation, is a perimeter foundation usually made from blocks and a shallow basement, usually two to four feet deep. There is not a concrete floor, but rather it is unfinished dirt or dirt covered in a layer of protective plastic. The perimeter foundation has a wood flooring system, often called the decking, over it, and the mechanical systems come up through the wood. While it is a shallow space, there is an access door so the homeowner and future contractors can access the crawlspace.
4. Basement With Foundation Forms
A basement with foundation forms is the most common choice for a foundation with a full basement. The foundation forms are used to hold the wet concrete in place until it dries. This is also called a "monolithic pour" because a large amount of wet concrete is poured into the forms at one time. Once the concrete has cured properly, the forms are removed and the construction of the home continues.
5. Basement With Pre-Fabricated Walls
The newest foundation is pre-fab walls that are manufactured in a weather-proof factory and delivered to the job site. The pieces are installed and secured year-round because there is no need to wait for weather that is warm enough for the concrete to cure properly. The finished product is visually the same; it is just where it is manufactured that is different.
While foundation talk may not be exciting, it is important to understand the different options available to you in your part of the country.