Memory foam mattresses have flooded the sleep industry and become one the most popular and advanced mattress types on the market. There can be quite a variation in terms of materials, construction, and quality. Below you’ll find the most important information to consider before you purchase a new memory foam mattress.
History of Memory Foam?
Density
The density of a mattress is a measurement of weight per one cubic foot of material, which is why denser mattresses can be heavier than less dense ones. How much heavier ultimately depends on the specific mattress and materials. Denser memory foams last longer and perform better than memory foams with a lower density.
ILD and IFD
ILD stands for “impression load deflection.” This is also known as IFD, or “initial force deflection.” ILD and IFD offer a standard rating system for indicating how hard or soft a piece of foam is. Simply, the higher the number, the more firm the mattress. The rating system ranges from 10 to 120, 10 being extremely soft and 120 being extremely rigid.
Firmness
Only the ILD or IFD rating indicates the firmness of a mattress. Don’t be persuaded by mattresses advertised as denser and thus firmer. Always look for the ILD or IFD number—only this tells you how firm the mattress is.
Composition and Construction
Memory foam mattresses vary in composition and construction. The more advanced mattresses are designed with layers of different foams. Christeli, for example, uses several different foams made from different materials and with a variety of ILD/IFD ratings. These designs ensure that each mattress provides optimal body support and durability along with a cozy, comfortable softness.
Response Time
Memory foam molds to the contours of a sleeper’s body, so response time refers to how long it takes for the mattress to regain its shape once the sleeper moves. If a foam resurfaces too quickly it creates pressure points. The same thing happens on a spring mattress: The mattress, especially in the hip and shoulder areas, is essentially pushing against the sleeper. You want a memory foam mattress with a slightly slower response time. This ensures your weight is displaced evenly and creates that wonderful pressure-free sleep environment.
American Made vs. Foreign Made
Although purchasing an American-made mattress is a great way to support U.S. workers and the U.S. economy, there are other reasons why these mattresses are a good buy. American-made mattresses are held to a higher, better enforced standard of quality. They are also made with the best materials. Foreign-made mattresses tend to have materials that can sag and loose that solid, "new mattress feel" more quickly. They typically off-gas as well, giving the mattress an unpleasant, chemical smell that takes a long time to dissipate.
Gel Memory Foam vs. Traditional Memory Foam
Mattresses made of gel memory foam are advertised to sleep cooler and provide better body support than traditional memory foam mattresses. Because of the plastic quality of gel memory foam, however, heat is trapped within the gel foam. The gel also acts like a spring, pushing back into your body rather than gently molding around it. Gel memory foam also breaks down much faster than regular memory foam.


