Laying the foundations for a small and simple addition is easy because the project is on a relatively small scale and you will be able to use the existing foundations to guide layout, leveling, and finishing details.

Types of foundations

Several types of foundations exist:

Concrete slab – it is an economical foundation type that allows you to finish the foundation and floor system, all in one operation. It also keeps the floor close to the ground.

Perimeter foundations – this a type of foundation that creates a low crawl-space under the house, the foundation walls are concrete block or poured concrete, it also supports a wood-floor system.

Full basement foundations – it is a good idea to excavate for a full basement in areas where conditions require a deep foundation. In this type of foundation the floor slab and the footing for the walls are concrete, but the walls themselves are usually concrete blocks.

Pier and grade beam foundations – this type of foundation is used for structures on steep hillsides or unstable soil, it usually requires professional engineering. This foundations system consists of concrete piers set deep into the ground and tied together by concrete beams.