November 2015

Science of mattresses

This is the section where we take our mattress geek credentials to new levels. In your journey to finding the right mattress, the science of mattresses will be wheeled out to baffle, confuse and wear you into submission!

Before you part with your hard-earned cash on that new foam or rolled mattress in a box you really should take a moment to ask what’s under the covers. If you know this detail theres no way to assess if its a suitable mattress model for you. We explain how to compare foam mattresses in this article.

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Understanding the science behind mattresses will allow you to make a more informed purchase

If you’re desperate to get the basics then please read our top 5 tips, for the more scientific and fellow geek readership, please inspect our foam data sheets.  They tell you everything you need to know about the foams we use at John Ryan By Design.

Foam Data Sheets

At John Ryan By Design we provide you with all the information you need to make an informed mattress choice.  Below are the data sheets, for the ultimate mattress geek, for all of our foams.  If you want to you can now go to the furthest comparison possible, providing the other mattress manufacturers will let you see their data sheets, we bet our bottom dollar they won’t though!  That’s where we are different, nothing to hide and no secret formulas!

Density of foams

As a rule of thumb the higher the density, the firmer the foam.  There are some exceptions such as reflex foam but if you use this as a guide when looking at retailers foam mattresses it should help.  Beware, many retailers probably won’t know the density of the foams!

Foam GradeFoam TypeDensity Min KG/M3Density Max KG/M3Hardness Min (N)Hardness Max (N)
Vasco 40Vasco Memory Foam38424060
Vasco 60Vasco Memory Foam587270100
Laygel 60Laygel Hybrid Foam5763100150
Coolblue 70Coolblue Hybrid Foam657070100
Reflex 300Reflex Support Foam3032100130
Reflex 300FReflex Support Foam3032130160
Knowing the exact density of a foam will indicate how firm it will feel
Knowing the exact density of a foam will indicate how firm it will feel
Without knowing the exact foam you're simply guessing when buying a memory foam mattress
Without knowing the exact foam you're simply guessing when buying a memory foam mattress

Top 5 mattress science tips

1- Off-gassing may occur with a foam mattress and is almost non-existent with a 100% natural latex mattress. Off-gassing occurs around the home in a number of products, new paint, kitchen worktops, new car smells to name a few. It is when chemicals are released or omitted from the mattress as a bi-product via volatile organic compounds (VOC’s). The only way to reduce it to a minimum it is with a 100% natural latex. The longer the mattress stays rolled up the stronger the off-gassing will initially appear. All of our mattresses are made to order reducing the time they spend wrapped up.

2 – Foams are made up of a number of chemical components which all react and are then aerated to create foam. Some people show concern about the amount and type of chemicals used. Memory foam has however been around for 20 years without any significant issues. Obviously, there will always be those who are sensitive to certain chemicals. If you are concerned about the effect of these chemicals or your sensitivity the only way to reduce the effects again is 100% natural latex.

3 – Fire retardants (FR) are mandatory in the UK and are there to protect you the consumer from products that are likely to catch fire. Cheaper exports may not have the same or any FR compliance. All of our mattresses are fully compliant. In the case of 100% natural latex, a thin FR layer will be added either side to ensure compliance without detriment to the feel and comfort of the mattress.

4 – Dust mites occur wherever there is moisture, warmth and dead skin. Whilst Latex is naturally dust mite resistant, it is your bedding, bed wear and home environment that will almost certainly allow dust mites to exist. Apart from having an intensive cleaning regime, we recommend you don’t pay over the odds for dust-mite prevention features as its a losing battle!

5 – Comfort zones in memory foam mattresses should be avoided unless the manufacturer or retailer can show you exactly how these are constructed. Many will simply be ‘Frankenstein’ mattresses of different foams stuck together. If you really want a zoned mattress you are better off with a pocket sprung mattress. Zoning in foam mattresses fundamentally breaks the consistency of a foam mattress.


It’s frustrating that so many memory foam and boxed foam mattress models won’t detail exactly what they contain. It makes comparing mattresses really difficult and unnecessarily so.

If you’re looking for guidance when looking for a new foam mattress why not speak to our experts to help?

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