5 Memory Foam Density Myths That Can Cost You Money

Memory foam density myths can cost you money on your memory foam mattress purchase. Do you really need to pay more for high density foam? Does low density foam last?

Memory foam density is one of the most important considerations when you purchase a memory foam mattress. But you could be paying more than you need to and getting less than you think.

Visco elastic foam density is measured in pounds per cubic foot (like a 12" x 12" x 12" dice).

1. Paying more for higher density foam is always a good idea.
   This is true. . . up to a point. Visco foam densities range from 2.5 lbs to 8 lbs. Most people are comfortable between 4 and 6lb densities. There's really no need to pay more for 6 to 8lb memory foam for a slight increase in mattress lifespan. And you'll probably sleep cooler too because denser foam traps more heat.
   


2. Memory foam density has no effect on how long your mattress will last.
   Wrong. A 2.5lb density mattress can feel the same as a 5lb one. You may not notice any difference right away. But the 2.5lb bed will lose its resilience or 'spring-back' because there's just not enough "stuff" to support the microcells over a long period. Foams that are not at least 3lbs dense can develop depressions within months of your purchase.
   


3. Denser foam equals greater firmness.
   Greater density has more to do with durability and longevity than firmness. High density foam can be very stiff or very soft, depending upon the manufacturing process.
   


4. Visco elastic density is the only thing you need to consider when choosing a memory foam mattress.
   Wrong. Many experts feel that Indentation Force Deflection (IFD or Indentation Load Deflection - ILD) is just as important when you're shopping. The ILD or IFD rating is a measure of 'firmness'. Measured in lbs/% compression. Usually ranges from 10 (soft) to 16 (hard). But most people will be comfortable in the 12-14 range. Unfortunately IFD ratings are often not available on packaging or websites. So be sure to ask.
   


5. All higher density foams are equal.
   Very wrong. There have been documented cases where density has been 'boosted' by heavier materials like sand. At best, these impurities make the foam denser, but cut or weaken the microcell walls that make up visco elastic foam. At worst these heavier materials can be toxic. Purchasing mattresses manufactured in countries with stricter consumer protection laws will usually protect you from these practices. Always make sure that you've purchased from a company with a good reputation and at least a 30 day no questions asked money back guarantee.

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