Memory Foam Mattresses. The Facts.

We all know how important it is to choose the correct mattress, as we all strive for the perfect nights sleep. This is even more relevant when choosing a memory foam mattress, or a visco-elastic foam mattress as they are also referred to.

Mattress construction

Memory foam mattresses are constructed of polyurethane and consist of a bottom or core layer. This is then covered by asofter top layer of memory foam that can be anywhere between 2-6 inches thick. The memory foam consists of billions of tiny air filled cells. Each individual cell retains a small amount of air which, relaxes under pressure, especially if the pressure is accompanied by heat. This is why when you lie down on the memory foam mattress the cells nearest to the top and your body will gradually release the air thereby producing an unusual effect whereby the mattress moulds to the shape of your body. Subsequently when you rise from the bed the foam cells gradually fill back up with air and return the mattress back to its original shape. Hence the name “memory foam”.


A substantial benefit of memory foam mattresses is the fact that they evenly support your whole body thereby, preventing stress on other areas of the body that may usually be effected such as your the shoulders and hips. Thus providing excellent support which allows your body to move naturally whilst asleep.

Another plus for the memory foam mattress is the fact that it is hypo-allergenic with anti-microbial properties which, is a huge benefit for those suffering with allergies or asthma.


The main disadvantage reported by users of the mattresses is temperature sensitivity this may result in the bed being quite firm, even at room temperature, and won't become more flexible and comfortable until your body heat warms it. It can also take a number of weeks to get used to sleeping on the foam. Another complaint about these mattresses is the strong odour when new, it takes some time for this to dissipate. It is recommended that you evaluate your memory foam mattress for at least one month.


The two most important factors to consider when making your purchase is firstly density and secondly firmness.

As there are numerous makes and brands on the market it can be hard to make an informed decision. The best guide to use when making this important purchase is to use the density of the foam. The density of the memory foam is measured by the weight of the cubic foot of the material i.e. pounds per cubic feet (lbs/ft3). The common densities range from 2 to 6 lbs/ft3.

For people who prefer a firmer mattress you should look at mattresses with a thinner top layer which, will subsequently cause your body to sink less into the mattress.


Although there are numerous manufacturers of memory foam mattresses, Tempur-Pedic, the Swedish mattress company are the more renowned. Tempur were the first company to evolve NASA's technology into use for beds. Other known companies who sell these mattresses are Sensus, Isoform, Isotonic and TrueForm.