Memory Foam 101

Foam Mattresses

A high-quality foam mattress will offer good pressure relief and support, conforming to your frame in response to your body heat and weight. Foam mattresses are made with a variety of materials; the most popular are viscoelastic, latex and polyurethane. Viscoelastic, commonly called memory foam, is the most expensive and most durable kind of foam. Less expensive polyurethane might feel comfortable at first, but over time the material can degrade and compress more quickly than viscoelastic. Unlike traditional innerspring mattresses, foam mattresses do not use springs to provide support, and they don't require the use of a box spring. Instead, an inexpensive slatted foundation can be used to raise the mattress to the appropriate height. Memory foam mattresses consist of a layer of 1 to 6 inches of viscoelastic glued to a high-density polyurethane base, whereas latex mattresses are simply a "slab" of latex foam in a cloth wrapper.

Memory foam comes in several densities; that's why you'll see a big price difference between premium brands and budget lines. Although foam density doesn't tell the whole story, in general, you want a higher foam-density of 4 to 6 pounds. Less expensive, less durable foam beds have a much lower density of 2 or 3 pounds.