An Introduction to Visco-Elastic Foam
What is Memory Foam?
Memory Foam is a visco-elastic foam originally developed by a Swedish company for NASA. It was used by NASA because of its ability to distribute pressure across the entire surface, thus easing extreme G-forces. It's also sometimes called slow release foam.
Memory foam was subsequently used in medical applications, for example where a patient suffered with pressure sores. However it was too expensive for general use and there were few if any suppliers in the home market.
In recent years viscoelastic memory foam has become cheaper to produce and is now widely available to buy for the home bedroom. You know something has reached the mainstream market when it's described as "As Seen On TV"!
Memory foam initially became popular in the US. It took a little longer to reach the UK, but is now becoming increasingly well known in the UK as well.
The most common applications are in mattresses, pillows and mattress toppers. Outside the bedroom, you can also buy memory foam cushions and footwear.
A memory foam mattress is usually denser than ordinary mattresses. This makes it more supportive - but also heavier. An alternative is to add a topper or pad to an existing mattress.
Memory foam comes in a variety of densities and various grades, the more expensive products often being referred to as premium grade.
When new, the foam does tend to emit an unpleasant smell.
What Does Memory Foam Do?
Memory foam is a temperature sensitive visco-elastic material. At room temperature it will mold itself to the shape of the body within a few minutes. Contrast this with a normal mattress that is simply flat. However well sprung, it will never precisely mold to the curves of a human body. Memory foam will also hold its shape temporarily - a hand pressed into it will leave a clear impression when removed.
As a result, a memory foam mattress or mattress topper will automatically adjust itself to your personal shape. In addition your weight will be distributed evenly across the whole mattress. This avoids painful pressure in one particular spot. (If you are suffering from a medical condition, always consult your doctor.)
In effect, memory foam does away with the need to compromise between a soft, comfortable mattress and a hard, supportive one.
Memory foam mattresses or toppers are sometimes recommended by physicians for people suffering from back pain. However you don't need to have a problem to benefit from - many people use them simply because they are more comfortable to sleep on. I was fortunate enough to have a friend tell me about memory foam some while ago and I'm a total convert.
Everyone needs a good night's sleep.
Memory Foam Grades
Memory foam is no longer the rare item it once was - today you can buy a bewildering array of brands and products at prices ranging from "not bad" to "ouch". How do you compare different offerings and decide which really is the best buy for you?
Unfortunately there seems to be no universally accepted method of grading memory foam for the consumer. This means that reputation of the manufacturer, personal recommendation and independent memory foam reviews remain important. That said, there are a couple of things you can look for.
There are two basic measures that can be used when comparing memory foam mattresses.
- The first is the thickness of the foam. This is probably of most importance when buying a topper or pad. A pad that is very thin is unlikely to give much support, a pad that is very thick is unlikely to be providing enough extra benefit to justify the cost. Most people find a thickness of two or three inches seems to work best.
- The other objective comparison is the density of the foam. This affects the amount of support given by the product. In general, denser foam will be firmer than the less dense variety. However foams of different densities from different manufacturers can have different levels of firmness (is there a word for that? firminosity perhaps?). In the US, foam density is usually described in terms of pounds per cubic foot. Common densities are 3, 4 and 5lb.
Premium Memory Foam
Some of the memory foam on the market is described as premium - but exactly what does this mean? There's no agreed definition, about the only thing you can be sure of is that if you buy "premium" anything it will probably cost you more! Whether or not it's worth the extra depends on your personal requirements.
What Is Premium Memory Foam?
In general, the word "premium" is normally used to refer to a denser foam. The denser the foam the more supportive it is.
Most memory foam products you can buy vary in density between around 2 lbs to over 5 lbs per cubic foot. Which is best for you depends on your personal circumstances including, for example, your weight.
If you're suffering from any medical condition then always discuss it with your doctor first.
As a rough guide, 4lb is usually considered "good" density foam, 3lb is considered "budget" and 5lb "premium". Remember, "budget" doesn't necessarily mean "bad" - 3lb density might be perfect for you. In addition, density isn't the only factor that will affect the feel of a product.
If buying a greater density does matter to you then don't rely on the word "premium" in an ad, always check the actual specifications.
Personally I have a memory foam mattress topper. It's fairly low density and certainly isn't "premium". However it does the job. That said, if money were no object then I'd probably try a denser foam.
So at the end of the day there's no clear method of comparing the quality of different memory foam products. The advice remains to shop around and remember that what's right for someone else might not be right for you.
Memory Foam Smell
For all its advantages, memory foam isn't perfect. One of its disadvantages is that when new it does give off a distinctly unpleasant chemical smell. This chemical release is known as off-gassing.
Whether or not this is a serious problem depends on the brand of foam you buy and your sensitivity to the smell. Few people are able to sleep with their new memory foam immediately they open it.
Personally I had to leave mine airing for about two days and even then I could still smell it slightly for a couple of days more. This seems to be about average. However some people find they need to leave the foam to air for a couple of weeks. Some are so sensitive to the smell that they simply give up waiting.
If you know that you're sensitive to smells in general then it might make sense to consider buying something small such as a memory foam pillow before investing in a mattress.
Incidentally, it is this smell that reportedly kept memory foam "earthbound". Visco-elastic foam was initally designed for the NASA space programme to cushion astronauts from the effects of acceleration. Apparently the smell was enough to scupper this plan. In a well-aired bedroom, the smell of memory foam might dissipate quickly and become negligible. But in a small cabin with recycled air it would be a distinct problem. And the astronauts could hardly open a window!
- What is Memory Foam
- Is all Memory Foam the Same?
- What Does Memory Foam Do?
- Why Not Use Memory Y Foam?
- Does Memory Foam Smell
- Do I Need to Rotate my Memory foam mattress?
- Where Can I Buy a Memory Foam Mattress?
- Can I Buy Memory Foam In the UK?
Memory foam is a common name for visco elastic foam. It has a fascinating history: it was initially developed by NASA for the space programme to help shield astronauts from high G forces. It is now used for bedding materials such as mattresses, pillows and mattress pads.
All memory foam does the same job, however as with all things there are differences in quality.
Different brands on the market vary according to their resilience and "bounce". This is reflected in the density of the foam from different suppliers - most of whom will tell you that their product is the best compromise between price and quality!
These differences are important for commercial or professional health applications, however for the average home buyer the variation between grades and brands can be marginal.
That said, you usually get what you pay for. If you buy the cheapest, unknown brand then you might get a bargain - or end up being disappointed.
Memory foam molds itself to the contours of your body, giving a uniform level of support. It is a good compromise between the comfort of a soft mattress and the support of a hard mattress. Some people - such as myself - find it the best way to answer the question of how to get a good night's sleep.
Memory foam is not for everyone. In particular if you have a back problem or other medical condition you should consult your doctor for information and advice. In addition some people are more sensitive to the smell of memory foam than others.
Yes - at first. When new, memory foam gives off an unpleasant chemical smell. You will probably want to leave it to air for at least a couple of days before using it. Some people are more sensitive to the smell than others and find it unpleasant even after a few weeks.
Memory foam will spring back into shape during the day, however as with all things it does slowly "tire". For this reason it is advisable to rotate your memory foam bedding every so often as you would with a conventional mattress.
When memory foam was first introduced it was too expensive for the average home bedroom. As it has become more affordable it has also become more easily available. You can now buy it from most specialist bedding stores or shop online.
Yes. A few years ago it was difficult to find - I remember trying. It's not a lot easier to get hold of and memory foam products are frequently featured in magazine and on home shopping TV channels. And, of course, there are many UK based suppliers online.
Despite the name, a memory foam mattress is rarely made out of pure memory foam. That would not only be very expensive but also probably not very effective. A pure memory foam mattress would probably be too soft for many people.
The memory foam itself also comes in different "densities" - the higher densities usually being more expensive. Again, more is not always better. A very dense foam might be too firm for some people who would prefer the softer, lower densities.
As you might expect, the relative thicknesses and densities of the foam varies between different manufacturers. That affects the price and also how firm and supportive the mattress is - it's an important point of comparison between brands. Since everyone is different there is no "best" thickness.
Some of the memory foam mattresses you can buy have a layer of memory foam on top of a supportive layer underneath. You can even buy some that are actually configurable with interchangeable support layers. This allows you to experiment to find the best option for you and also to review your needs at a later date.
It's a confusing market with so many combinations. As always the best option - if it's practical - is to try out the mattress yourself at a store before buying.
If you already have a good quality mattress then an alternative might be to consider buying a memory foam topper (pad). This also gives more flexibility - if you decide you made the wrong choice of foam then you can just change the topper without having to change the entire matteress. But even a luxury topper won't save an old, sagging mattress!
This site is meant to be used as home-base for anyone looking to purchase a memory foam mattress. Memory foam is such a complicated product. There are dozens of manufacturers of memory foam, and with the advent of lower cost Asian foam in the past six or seven years, it has caused many to wonder “Is all memory foam the same?”
The answer is No. All memory foam is not the same. And to complicate matters, not all memory foam retailers are the same. This page will help you easily identify the quality companies and types of memory foam on the market, in addition to providing a wealth of information on memory foam, its history and its applications.
History of memory foam
Memory foam is one of the better known types of foam today, and hasbecome a very important part of the bedding industry in recent years.
There is much folklore behind memory foam being a NASA developed product. This is true, but only to an extent. In the early 1970’s, NASA engineers produced a type of foam called T-foam.
The idea was to make a foam that could be used in the seats and suits of astronauts, to help reduce the negative affect of high g-force pressures on the body. T-foam was the predecessor to the memory foam we are familiar with today.
Unfortunately, T-foam was never used in the space shuttles. So the technology sat there, unused for a long time. One day, somebody stumbled upon the possibility of a consumer application for the foam and set about redeveloping the technology. After years of research they came up with what is the memory foam we are familiar with today.
Initially this was marketed as Swedish memory foam. The company that came up with it was Tempurpedic.
Tempurpedic, widely known today had very humble beginnings. They opened a store in the Midwest in a small shopping center. Though profitable, the store was not doing unbelievable sales. At this point Tempurpedic was the only company marketing memory foam. The year was 1992.
What the company realized is that if they were to become large, they were going to have to develop a new way of distributing their product. Other mattress stores just wouldn’t carry them; there wasn’t enough demand.
So the company, with significant venture capital involved at this point, developed a very sophisticated direct marketing campaign. This consisted of 30 minute to 60 minute infomercials. The infomercials were played late at night when most people that had trouble sleeping were still up. Though very costly, the campaigns proved to be successful.
Tempurpedic had accomplished something that nobody had to done before in the mattress industry, selling to consumers without having the customer try the bed first. The catch was they would have to offer some sort of trial period, in which people could get at least a percentage of their money back.
This strategy was played for about 5 years, with literally no competition from other companies. It got to the point where this market could no longer be ignored because of its growing size, thus the competition entered. Initially, the competition’s memory foam was far inferior to Tempurpedic’s foam. Where as Tempurpedic was marketing 5.3lb memory foam, the competition used 2-3lb memory foam and the difference was very apparent.
Over the next few years, the competition became greater and greater and there were even Chinese manufacturers that entered the mix. At this point, the quality of Tempurpedic alternatives really took a dive. Clay and all types of harmful chemicals were being mixed in with the foam. On top of adding chemicals people were misrepresenting the products they were selling.
Fortunately, in the last few years the domestic memory foam market has caught up with Tempurpedic. You still need to be wary of things like density and whether it is 100% viscoelestic memory foam or not ( memory foam buying guide ). There are domestic alternatives that are just as good, in some cases better than Tempurpedic.
Today memory foam can be found in all major mattress stores. The market accounts for about 10% of mattress sales each year. In most mattress stores you will find Tempurpedic mattresses along with a low end, low density memory foam mattress that is carried to hit a certain price point. You will not find memory foam beds with foam of the same density as Tempurpedic’s in stores. We’ve been told by certain dealers that this was a part of their dealer agreement with Tempurpedic. A good place to get memory foam of the same quality as Tempurpedic is right here on the internet.
(See our ratings of online memory foam stores here)
Memory foam is even sold in big box retailers, such as Wal-mart and Target today. You can buy it on airline catalogs and airports, as well as over the phone. We recommend doing your homework and you’ll end up with a good product. Our website is packed with real reviews of retailers, both online and off, and of buying information, as well as answers to even the oddest memory foam questions you may have.