Bed base

A bed base, sometimes called a foundation, is the part of a bed that supports the mattress. The bed base is itself held in place and framed by the bedstead (bed frame). In the United States, box spring bed bases are very common (to the point where 'bed base' and 'box spring' may be used synonymously). In Europe, sprung slats are much more common.

There are three main types:

Typically the measurements of a foundation will be about 1-2" shorter than the measurement of a mattress.

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