Memory foam mattress guide

Find out which memory foam mattress is best for you

memory foam mattress tempurMemory foam mattresses started out being used in hospitals to help people who were bed-ridden for long periods. Often such people end up with bed sores or pressure sores and memory foam – initially developed for the space programme – was seen as a solution.

People using the mattresses soon started reporting that they felt they were sleeping better and suffering from fewer back and neck pains and after that it wasn’t long before mattress producers saw a gap in the market for selling the mattresses to joe public to help with back pain.

Memory foam reacts to temperature – the warmer something is that’s touching it, the softer it gets. Then, when the heat source goes away it regains its shape and structure. So, the parts of your body that press against the mattress cause the foam to heat up and become soft, allowing your hip and shoulder, for example, to sink down into the mattress keeping your spine straight.

The mattresses are now popular around the world and many people benefit from them as a way of relieving pain or use them simply to get a better night’s sleep. The only downside of these mattresses is the cost – they are generally significantly more expensive than a ‘normal’ mattress so if you’re thinking of buying one then you want to make sure you get the right one to suit you.

This guide aims to give you some tips on choosing the right mattress and making sure you know what to look for when you go to buy one.

The first thing you will notice when you sit or lie on a memory foam mattress is that it seems quite hard. That’s because the memory foam is quite hard – until it starts to react to your body temperature. As a result you can’t really tell if it’s suitable for you simply by lying on it for a minute or two; you need a couple of other things to help you out in choosing.


Every memory foam mattress will be made up of different layers of foam. The top layer will be memory foam but underneath that will be ‘normal foam. This is necessary to ensure the mattress retains its overall shape. There are some key questions to ask when looking at a mattress:

What is the IDF of the memory foam?

The IDF (Indentation Force Deflection) is the measure of how much ‘give’ there is in the memory foam. IDF figures range from about 10 to 16 with the majority of foams measuring between 12 and 16, with 10 being very soft and 16 very rigid. Unless you have a specific reason to go to the extremes you are probably better off going for something around a 12.

What is the density of the memory foam?

Different foams also have different densities and the more dense the foam the better the quality. Density ranges between 1 and 7 lbs per cubic foot; most mattresses are in the 3.5 to 4.5 lbs per cubic foot. Densities of 5 lbs and above are considered very high quality and these will last longer and perform better than less dense versions (they will also cost more).

How thick is the memory foam segment of the mattress?

As stated above a mattress made wholly of memory foam would soon lose its form and supportive structure so mattresses are usually made up in a sandwich construction. The depth of the memory foam section will have a bearing on the performance of the mattress. Anything less than 2 inches will probably be a waste of money; equally, anything more than 6 inches would be over the top. The only time to go for something thinner than 2 inches is if the density is very high and there is a specific reason you have been advised to look for such a mattress.

What else you you need to know about memory foam mattresses?

They can be beneficial from people who suffer from asthma

Because the foam is closed cell there is less opportunity for bed bugs and dust mites to shelter in the mattress.

They don’t sag or move when your partner rolls over

This can be a real bonus if you’re a light sleeper or have a restless partner. Because they are naturally firm and there is no underlying set of springs any movement on the mattress is reduced. One partner can even get into or out of bed without the other feeling it.

New mattresses might smell a bit

Some new mattresses have a distinctive foam smell; although this is harmless it can be a little unpleasant. If possible, when you get a new mattress remove it from all the packaging and put it in a well-aired place (a spare bedroom, for example) for a few days to let it vent off.

What’s a memory foam topper?

A memory foam topper is a cheaper way of getting the benefits of a foam mattress. Rather than replace your whole mattress you simply buy a topper which is the memory foam on its own, with no supporting foam structure, and stick it on top of your old mattress. If you have a firm, supporting mattress already this can still give you the benefits; however, if your mattress is old and lumpy then it really won’t help – especially if you’re buying a mattress for health reasons. Use the same advice when buying a topper as when buying a full mattress, comparing depth, density and IDF.


Memory foam is quite heavy and your memory foam mattress will probably be a lot heavier than your present mattress. So, make sure that the structure of your bed can take the additional strain. If the structure is bending and flexing then you will lose some of the benefits of the mattress.


Be aware that you can’t use a memory foam mattress with an electric under blanket as that will negate the benefits of the memory foam by making the whole mattress soft. As a result it can sometimes be a little chilly when you first get into bed but it soon warms up. Once warm some people find they can actually get too warm as they retain a lot of the body heat that would usually be dissipated

Who’s the memory foam market leader?

Tempur® were the original makers and this Swedish company still leads the way today. They are generally agreed to provide the best quality and, because they are still involved with making medical products, their consumer products benefit from the same high level of research and development. One thing that Tempur® used to do (and probably still do) is allow you to trial a mattress for a period of time (a month, I think) before buying. That allows you to get a good idea of how you will get on with the memory foam mattress concept. (I would like to say here that I have no connection with Tempur® apart from using one of their mattresses for the last 8 years; I can say from personal experience that they are good and long lasting).


The old adage that ‘you get what you pay for’ rings very true in the memory foam mattress world. There are a lot of companies out there producing what they call memory foam mattresses and selign them at a very cheap price. One of the reasons why memory foam is so expensive is because it’s expensive to make so the chances are that a cheap version isn’t the real thing. If you’re unsure about the high cost outlay of a mattress then try a topper (provided your present mattress is suitable); you could move on to a mattress later. Personally, I’ve found our memory foam mattress to be excellent; I suppose the biggest test is ‘would I get another?’ to which the answer is a resounding ‘yes!’

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