You can’t put a price on a good night’s sleep. Your daytime performance is highly dependent on how well you were able to sleep the night before. Since you came here in search of a memory foam mattress buying guide, you have likely made your mind up on opting for a memory foam mattress, instead of a latex, innerspring, hybrid, air or water mattress. Congratulations! You’ve made the right choice. Memory foam is soft, yet is ultra-supportive and conforms to your body like a glove. Importantly, it is able to regain its original shape once you get out of bed. Memory foam melts upon sensing your body temperature and cradles the whole body relieving pressure on the hips, shoulders, back, and neck. In addition, it also results in very good alignment of the spinal cord, greatly enhancing healthy, uninterrupted rest. Our memory foam mattress buying guide will walk you through the most important things you need to look at when selecting a mattress. Here are the major criteria you need to pay attention to, when buying your new memory foam mattress.

Gel-infused memory foam or not?

As we underlined in our Pros and Cons of Memory Foam Mattresses, one of the major complaints against memory foam is their heat-trapping characteristic. As a result, consumers have found memory foam mattresses to sleep a tad bit too hot, especially during warm, summer months. However, memory foam was too good a material to give up on based on its ‘heaty’ properties; therefore scientists worked day and night to find a solution to this problem. Peterson Chemicals gets the credit for coming out with a solution to the above problem. Their researchers found that infusing a type of gel into memory foam enhanced thermal conductivity of the polyurethane making it ‘cool’. Ever since, mattress manufacturers have embraced this technology to produce cool gel memory foam mattresses. Unless you’re living in Alaska or Maine, I strongly suggest that you go with a gel-infused memory foam mattress. These gel particles typically add a hint of blue color to the memory foam.

WTH is ‘Open Cell Technology’?

That certainly sounds like an advanced rocket-science like technology. But fear not, it’s a simple technology that was recently introduced to further cool down memory foam. Some manufacturers, in addition to using cool gel particles, or sometimes instead of using cool gel particles, use what’s known as ‘open cell technology’ to further cool down their mattress. As you know, memory foam and all other types of foam are referred to as ‘foam’ because they have a foamy texture. If you look closely, all foam mattresses (memory foam, poly foam, adaptive foam etc. etc.) are made of tiny ‘cells’ with thin outer walls surrounding an air bubble in the middle. These ‘enclosed’ cells are one of the reasons why memory foam becomes a little hot at times. The ‘heated air’ gets trapped inside the cells and have no way of escaping; thus warming up the entire mattress. With the relatively new ‘open cell technology‘, the cells aren’t enclosed anymore. Adjacent cells communicate with each other allowing the heated up air to escape the cell, into the surrounding cells and then, eventually, out of the mattress. When the hot air gets out of millions and millions of cells that make up a memory foam mattress….. you guessed right… the mattress cools down. Some modern memory foam mattresses are able to regulate heat entirely with open cell technology and a network of grooves that ventilate the mattress sufficiently. So in essence, if you’re concerned about the ‘sleeping hot’ nature of memory foam, look for a brand that has A) gel-infused memory foam AND/OR B) open cell technology.

Why does memory foam density matter?

A picture is worth a 1000 words… in this case, it might be even more…
We have defined low, medium and high-density values as <3, 3-5, and >5 pounds per cubic foot. However, these cutoffs can vary depending on the source you refer to. There is no reason to get hung on these numbers; just understand how the dynamics change as the density goes up and vice versa. Those with SEVERE back and joint pains (and extra ca$h) may consider high-density memory foam mattresses. Orthopedic mattresses generally belong to this category. For everyone else, medium and low-density memory foam would work just fine. Even if you had back, joint, and muscle issues, a medium density mattress can do wonders, as long as the pains are not in the ‘severe’ category.

Should you worry about ILD ratings when choosing a memory foam mattress?

The simple answer is “NO”; why so in a minute!

First of all, what is ILD?

ILD stands for “Indentation Load Deflection”. It is sometimes known as Indentation Force Deflection (IFD). It is a measure of “amount of load/force needed to indent the foam by an inch”. Following is an exact definition of ILD.
ILD is the force (in pounds) required to indent a 50 square inch disc into a memory foam block measuring 15″x15″x4″ to make a 1″ indentation. Therefore, a mattress with an ILD of 15 would require 15 pounds of weight to indent it by one inch.
Here’s a video of how they actually test ILD. As we’ve mentioned earlier, memory foam density is NOT an indication of the mattress firmness. However, ILD is a direct indication of the memory foam firmness. Therefore, you can assume that a mattress with an ILD of 15 to be firmer than one with an ILD of 12. But not really! Really? Why on earth is that?

Don’t worry about ILDs when picking a mattress!

That’s because any memory foam mattress you buy at a store is NOT memory foam in its entirety. Usually, only the top layer (2-3 inches) is made of memory foam. The bulk of the mattress is made of a support/base foam which is non-memory foam. It doesn’t make sense to judge the whole 10 inches based on the ILD of the top 2 inches! That’s why it’s pointless to worry about the ILD of the top portion of the mattress. It’s really that simple, I hope you understand that and stop worrying about ILD (if you have been). Instead, (1) rely on your first hand experience, by lying on the mattress of interest, or (2) rely on trustworthy reviews of actual customers.