What about carpet cushion?

The cushion under your carpet is one of the most important considerations when buying new carpet.

It is the base that helps the carpet retain its texture and appearance.

A cushion is sold by its thickness and density.

A pad that is too soft will adversely affect the performance of the carpet, and a pad that is too thick interferes with the anchoring of the carpet.

For residential installation, a cushion of no more than 7/16-inch thick and no less than 1/4-inch thick with a 6 pound per cubic foot of density or equivalent is recommended. (A cushion of 3/8-inch thickness with a 6 pound per cubic foot of density or equivalent is recommended for berber style carpets.)