A Primer on Memory Foam Mattresses

The last time you purchased a new mattress, there were probably fewer choices, but today, there are many more options available. Memory foam mattresses, new to consumers in the last twenty years, are an excellent option for today’s shopper. Having some basic information will help you make a proper comparison between the different types of mattresses available.

Memory Foam Mattress Basics

A Brief History

NASA originally developed memory foam as a way of protecting astronauts in the late 1960’s to early 1970’s. In the 1990’s, memory foam became available to consumers in the form of a mattress. Since then, the technology has evolved and been extended to pillows.


How are Memory Foam Mattresses Constructed?

All memory foam mattress construction begins with a strong support core which is all foam and helps to provide a balance between support and comfort. The top layers of the mattress are constructed of memory foam and some combination of manufacturer-specific fibers and foams. These differences provide different levels of comfort and cooling.

Memory Foam Terminology

Memory foam terminology is a bit different than the mattress terminology you might be accustomed to. It’s important to understand these unique terms in order to make comparing memory foam mattresses more meaningful.

  • Viscoelastic
    Memory foam has a quality called viscoelasticity. In layman’s terms, this means memory foam is viscous and it is elastic, all rolled into one. But what is viscous and how does an elastic property make a difference? To put it simply, the viscous property allows the mattress to be firm. The elastic property allows the mattress to have some bounce-back, but not too much.
  • Density
    Memory foam comes in different densities. A higher density will provide you with a firmer mattress. When you see something like “5-pound density”, it means one cubic foot of the foam weighs 5 pounds. A denser mattress will have a higher price. You will have to try out different densities to determine whether you need a higher or lower density.
  • ILD Rating
    The ILD (Indentation Load Deflection) refers to how hard or soft the foam is. It can get rather complicated, but here is how it goes. The ILD rating assumes that you are attempting to place a 50 square compression on a 4” thick piece of foam. Twenty-pound ILD foam is a foam which requires 20 pounds of compression to make a 25% indentation (25% ILD Rating). Higher ILD foam is denser.
  • Resilience
    The resilience of a memory foam mattress indicates how ‘springy’ it is. Resiliency is determined by measuring how much rebound occurs when a steel ball is dropped from 36”. Higher resiliency (H.R.) indicates better and more durable foam.

ca13_ass_600_300Comparing Mattresses

With the above information in hand, you are now ready to make some comparisons. This information enables you to compare different types of memory foam mattress reviews anno 2015, but what about the differences between memory foam and mattresses made of different materials or in different ways?

Memory Foam Compared to Inner Spring

Several comfort comparisons have been made between inner spring and memory foam mattresses. In one study, conducted by sleep research website, Sleep Like the Dead, owners of memory foam mattresses were more happy with their mattress than owners of the older-style spring mattresses. Eighty-one percent of memory foam owners were satisfied with their purchase, compared to 63% of spring mattress owners.

Nothing, and I mean nothing, compares to memory foam in how a mattress conforms to your body. Inner-spring mattresses regain their original shape as soon as you get up, but memory foam mattresses conform and maintain your body shape, long after you get up. This happens because, when compressed, the air in the cells of a memory foam mattress take up residence in nearby cells and the air stays in its new location. Inner spring mattresses redistribute the air, depending on the weight being applied.

For those who suffer from arthritis or another form of joint pain, memory foam mattresses provide excellent support. Since the foam conforms to the shape of your body, it does not force your body to remain in an unnatural position like an inner-spring mattress will.

Latex-MattressMemory Foam Mattress or Memory Foam Pad?

If your current mattress is not quite ready to be replaced and you’re interested in trying memory foam, buying a less-expensive foam pad might be a good option, but if you are in the market today for a new mattress, you should splurge and go for the mattress, rather than just the topper.

Memory Foam versus Latex Foam

If you have a latex allergy, this is a no-brainer, and for those with a latex allergy, you should take into consideration that some memory foam mattresses actually contain some level of latex. A latex foam mattress will have a higher level of elasticity and resiliency than a memory foam mattress. What this means to you is latex will push back against you a little bit when you lie down, where memory foam gives more of a feeling of melting into the mattress.

Memory Foam or Air Mattress?

You may have heard of a popular air mattress which allows you to dial up your level of comfort. These are, at their core, air mattresses. The only, and I mean only, benefit to this type of mattress is that each sleeper can dial in their own level of comfort. These mattresses, however, come with poor warranties due to the number of moving parts that can easily break. A memory foam mattress also allows both sleepers to have their own specific comfort level and warranties on high quality memory foam mattresses extend as far as 20 years out.

How to Decide

  • Price
    If price is a concern, you should know that a memory foam mattress, on average, is priced nearly equal to inner-spring mattresses.
  • Comfort
    As mentioned previously, owners of memory foam mattresses report being as much as 18% more satisfied with their mattresses than owners of inner spring mattresses.
  • Longevity
    Memory foam mattresses have a much longer life span than inner spring mattresses, which generally have about an 8-year lifespan. As previously noted, memory foam mattresses last much longer if properly taken care of.

The Final Decision

Buying something that will last you 10-20 years requires a lot of consideration, but armed with all of the information above, making a final decision should be much easier. Once you have determined your price point, you can head out to try some different foam densities and see what feels good to you. If you want something which will last you well into the future, choose the highest quality memory foam mattress you can afford.