Foundation
Foundation is an architectural object in The Sims 2 and The Sims 3.
It is used to raise the level of the main floor and can be used over uneven terrain. It also helps in the construction of basements.
The foundation tool is used by clicking and dragging an a square area on the terrain. There is also a diagonal foundation tool.
Players can choose either a decking foundation, an elevated foundation, or a brick foundation.