Foam mattress construction

The simple fact about memory foam and latex mattresses is that they look incredibly simple to design, but, in reality, are very difficult to get right! Some would say its a piece of cake! Anyone can stick a few layers of this and that together, but you need to fully understand the materials, benefits, drawbacks and science behind it to get it right. That’s where we come in.

Hybrid 4 cheese

The general rule is that a mattress should start off at its firmest at the base and then each layer should get progressively softer, until the topper layer. This allows for progressive comfort and enables the mattress to support you as you sink into each of the layers. If the mattress is too soft for your weight, you will sink quickly down to the firmest layers resting solely on the supportive base. If the mattress is too firm you will simply sit on the top layer without benefiting from the other materials.  Both scenarios result in an uncomfortable mattress. The correct mattress will allow you to sink into the layers and equalise, i.e. it is holding, supporting and comforting you just at the right level, not sinking too deep, not resting too high.

Most foam mattresses rely on reflex foam as the ‘support’ layer which is the white foam in the above image. Some foam mattresses may use FEPS and we have an article on that here. The reflex foam is then layered with other softer foams.

It is the foam layers above the reflex foam that you should pay the most attention to understanding their depths and densities is key to fully assess and compare the models you are looking at. There’s an example data sheet for the foams we use that can be used as a comparison to the foams you may encounter.  We have a much more detailed article on how to understand depths and densities of foams here.

Foam GradeDensity Min KG/M3Density Max KG/M3Hardness Min (n)Hardness Max (n)
Vasco 40kg38424060
Vasco 60kg586270100
Laygel 60kg5763100150
Coolblue 70kg657070100
Reflex 3003032100130
Reflex 300F3032130160

The problem of the no turn foam mattress

Given that Memory foam, Hybrid or one-sided mattresses can’t be fully turned like a traditional mattress, we have devised a product which minimises this drawback and provides you with a more durable and flexible mattress construction.


All of our Hybrid and Latex mattresses come with our dual construction method, not seen in many of the retailers with the exception of Jensens high-end Latex mattress range. This consists of a high-quality hybrid or latex mattress base with a complimenting removable topper. This means that you can rotate and turn the topper when you normally would turn your mattress.

The mattresses have been specially created with this in mind to give you not only a superior mattress in terms of comfort, but the option to turn your matching topper and change it later down the line should you need or choose to.

What’s the benefit of the dual construction and topper?

Quite simply you can turn your mattress topper which should reduce compression and allow you to extend the life of your bed. It also means that in the future should your body weight change, preference for a firmer or softer bed change, you can replace the topper and continue to use the base. It’s far more cost effective to replace this topper than an entire bed.

In addition to this, it allows our mattresses to offer more of a progressive comfort when compared to the standard two or three-layer construction methods. The increased depth and layering offers more comfort, as memory foam requires a certain depth, usually 5cm to really provide comfort, something that is paramount. We offer 5cm as a standard depth, compared to 2-4cm in other standard mattresses and on top of this our toppers are also 5-7.5cm meaning you are getting much more mattress for your money.

Comparing depths of foam mattresses

If you compare our mattresses to standard construction mattresses you will see our mattresses range from 25cm (10inch) to 30cm (12inch) across the range. We, therefore, recommend that extra deep fitted sheets are used as they are higher than a standard mattress.

For comparison, the following market leaders of  memory/hybrid foam mattresses depths are:

  • Tempur – 19cm to 25cm across their range
  • Ergoflex – 21cm standard depth of their one range
  • John Ryan By Design – 25cm – 32cm

Cheaper memory foam mattresses usually start at 15cm overall depth with only 2cm of memory foam. Again, we are providing you with the facts to make your own decision, remembering it is not just the depth but the construction and density of the foams that will determine the suitability and quality of the mattress.

Can I use any shop bought topper for this?

The simple answer is Yes! But you will again run into a myriad of questions about the quality of topper, materials used, and firmness rating. Here at John Ryan By Design, we have undertaken significant research to match our topper with our mattresses for you and can provide advice on what is suitable for a certain type of mattress. We only sell the highest quality toppers with generous depths to ensure minimal compression and the longest lifespan for the type of bed.

Top 5  Foam Mattress Construction Tips

1 – A no-turn mattress is not a benefit, but a requirement of the foam construction method.  The softer foam, such as memory foam, sits on top of the reflex foam, firm supportive material, and this makes the mattress one-sided. To turn it would damage the mattress. Don’t be duped into thinking this saves you time.  Our range all come with dual construction fully turnable toppers to extend the life of your mattress.

2 -Memory foam and other foams will all compress at some point as they ‘bed in’. It is not always a bad thing providing it is minimal and consistent. The cheaper the material the quicker and more prominent the compression. Minimal compression is known as bedding in. A compression that is over the accepted 2cm amount is known as dipping where the bed has failed you.  You should always be looking at 5cm plus for your Memory foam layer so that the compression is minimal. The thinner the layer the more prominent the compression, so a 2cm Memory foam layer that compresses by 2cm will fail to have any purpose!

3 – There’s a huge branding exercise around the material your bed is covered in from infrared to anti-dust mite which has little impact on your sleep, the money they cost is best spent elsewhere. A removable fire retardant polyester cover is fine for a memory foam or latex mattress since it will be covered by your fitted sheets. You can always take this off and wash it as part of your maintenance routine. You are better off spending your money on a decent set of cotton fitted sheets and duvet covers instead where you will feel the benefit.

4 – We recommend that you rotate a no turn mattress monthly if possible to reduce compression. All of our dual construction mattresses come with fully turnable toppers that can be rotated and turned to extend your mattress life.  All mattresses should be turned, flipped and rotated where possible.  Failing to do so may result in dips, lumps or reduced longevity for your mattress!

5 – A solid core latex mattress is the king of latex mattresses and can be turned and rotated. This is why they command a higher price but are ultimately much more durable. Make sure you ask if your latex mattress is solid core, most are not.  Our Fusion range of mattresses are all solid core and fully turnable


The very construction method of foam mattresses means that 99% of them are one-sided, with the exception of solid core latex such as our Fusion range.  Foams, like all upholstery, will compress and settle over time.  The accepted amount is 2cm. This means that rotating the mattress monthly and the inclusion of a topper are essential to keep the mattress in prime condition as long as possible.  If you don’t rotate and keep sleeping in the same spot the likelihood is you will end up with indents that you then can’t remove.  Call our friendly team if you need more foam mattress help.


View Comments
  • Comment via email says:

    I suffer from back pain and I’ve been advised by one of the main bed retailers to go for an orthopaedic mattress in a firm tension? They said this would help with my spine problems? Can you advise what kind of bed I should therefore choose to help reduce my back pain?

    You’re correct that with a back issue you do require support. The industry has taken this to mean really firm beds, as if that will some how ‘straighten’ out your ailments. This will just lead to discomfort. What we recommend is that you need an adequate match of support, without it being so firm you feel like you’re on concrete, and comfort ie softer top layers. With latex for example, you will get an initial sink, the comfort factor, before the support kicks in. People often equate firm to solid and this is also incorrect. Lets take the latex example. A firm latex will be supportive and firm but not solid. This is because although its firm its not like a cheap ‘firm’ solid bed ie springs that are far too firm and cheap dense reflex comfort layers. We also match our latex range with medium toppers to give that lovely comfort soft top feel but with the support underneath.

    As for bed retailers stating this will help your back issue, be careful. Unless its your doctor or chiropractor then I wouldn’t take any assurance that a bed will ‘fix you’. What you can do however is take advice on how the bed will react and feel for you, as we do, to make your own informed choice. There is no one size fits all so please get in touch with us at John Ryan Contemporary for more assistance. Ultimately a high quality bed should allow you to find a comfortable position, down to the comfort layers, then be supported there so you don’t sink too far or rest too firmly on the mattress. Lee

  • MARK says:

    I’m interested to know if you could manufacture me a bespoke mattress based on the specifications of a well known mattress I want but think is over priced. Is this something you at John Ryan can do through your bespoke mattress section? Mark

    Hi Mark, The simple answer is no. I would never simply copy or replicate another mattress. Decent companies spend considerable time designing and testing them. I also wouldn’t take their specifications as gospel, my mattresses have all been made to our bespoke designs at John Ryan Contemporary that we have tried and tested. We are old fashioned that we would never take someone else work as I’m sure you will understand. Lee

  • Sarah says:

    I am looking for a new kingsize mattress to replace our 15 year old Sealy Posturepedic which has been very comfortable until quite recently and hope that you can advise me. My husband is 94 kg and has a partially prolapsed disc in his lower spine. I am 47 kg and suffer from problems with my right hip and shoulder and neck which is most definitely exacerbated by our current mattress. I am also sensitive to chemicals so do not want anything which will outgas too much, the more natural it is the better. I am looking at a latex mattress because of the power relieving properties but am not sure if this is the best option for my husband’s back problem or the weight differences, perhaps one of your traditional ones would be better? We are both mostly side sleeper but do also sleep on our back and fronts, my husband does not like anything too soft and I don’t like anything too firm. The mattress will sit on a pine slatted bedstead.

    Any advice you could offer would be greatly appreciated and I look forwards to hearing from you.

    Hi Sarah From what you have described in your email, and both your preferred feels, it is unlikely you would find a Latex mattress to achieve this. Because your husband at his heavier weight, not wanting a soft feel, would want a firmer feel mattress, then you would find that extremely firm. Also if you got your softer feel mattress, at his heavier weight this would be extremely soft.

    The only way you will both achieve your desired feels, is with a traditional zip link mattress. Please have a look at our zip and link Artisan models on our John Ryan By Design site and get in touch. Gary.

  • Nessie says:

    I need a mattress and pillow topper for a king sized bed. I have a shoulder injury and am a side sleeper so the mattress must have excellent support on the edges – no squishing down or collapsing. I prefer a pillow top for comfort but on a firm base. Any suggestions

    Hi Nessie,

    We don’t recommend pillow top mattresses for the simple reason that once the pillow top compresses theres no way to remove or replace it. This leaves the entire mattress pretty much useless. We always recommend removable replaceable toppers for this very reason, and all of the contemporary mattresses come with a removable matching topper.

    I would need to know your weight /height to provide a accurate recommendation Nessie. If you are looking at contemporary mattresses then you won’t find one with firm edge support. The reason for this is that latex and foam mattresses provide consistent level of support and comfort from the centre to the edge. Adding firm foam around the perimeter introduces more materials that can over time start to degrade or settle at a different rate to the main foam / latex. This can lead to issues with settlement. If you’re wanting a more traditional mattress please look at our John Ryan By Design range at It maybe easier if you give us a call and we can help narrow down your search further on 0161 437 4419.- Lee

  • Jeremy says:


    Firstly many thanks for your incredibly informative websites.

    My query is that whilst I prefer natural materials, I’m not sure how to compare latex against traditional construction. In particular, I’m wondering about the Fusion Zero Firm against the Artisan Naturals, the former of which is on your contemporary site and the latter on your original site, so it’s difficult to make comparisons.

    I currently have a traditional style king size 10 year old 1000 pocket spring Hypnos Mattress purchased from House of Fraser which has recently lost some of its support. I sleep alone and I’m just over 6 feet tall and weigh about 12 stone.

    In terms of budget, I’m looking to make my money go as far as possible so I’m particularly attracted to models available from your Outlet. The Fusion is the lower cost option which is a consideration, but also I want whatever I purchase to last as long as possible.

    Thanks for any advice.



    Hi Jeremy, Thanks for getting in touch and asking one of the most frequent of questions! What’s the difference between a traditional mattress and a contemporary latex mattress?

    The answer is that they are very different in the way they react and behave for a sleeper. Most people have a definite preference for one over the other. Its very subjective.

    The traditional style of mattress usually, I say usually as there are exceptions, has a more robust feel to it overall. Ie perimeter support gives a firmer edge and the mattress itself can have softer top layers they are not as progressive in terms of sinking. The sink is slower and more forgiving without fully moulding or contouring to you. Traditional mattresses can also be two sided, turnable where as some of the contemporary models by very nature are one sided.

    The contemporary latex or foam mattresses have a more uniform look, i.e. there are usually no tufts and so no way that the top layers can move about and away from one another which sometimes can happen with a traditional mattress over time. The contemporary mattresses usually don’t have a firm edge as the entire comfort surface is the same tension, this allows great progressive comfort, i.e. sinking followed by support. This means they usually contour more than a traditional mattress. The foam mattresses however do get warmer than traditional ones and are usually one sided only, meaning you can only rotate your mattress.

    As for longevity, it depends on the maintenance of your mattress, how consistent your weight is over time, i.e. if you suddenly put on 5 stone the lifespan may decrease due to excess stress on your mattress etc.

    The two mattresses you’re looking at are very different, the fusion zero is a very firm mattress the artisan naturals is a very medium feel in the top layers and can have a tailored tension spring in our full price model. It maybe best to give us a call, 0161 437 4419, to get some more details to assist you Jeremy.

  • Jenny says:


    I am looking for a mattress for my son’s bunk bed the dimensions are 80 x 190 (depth 15-16cm). Do you have any products that might be suitable?


    Hi Jenny, I’m afraid we don’t sell such a shallow depth of mattress. This is because our range are all incredibly deep to provide you with the highest quality mattress that will last. I understand bunk beds cause height issues with really high mattresses my advice would be to maybe look at Ikea whose range is good quality for money for this purpose. Hope that helps – Lee

  • John says:


    I am interested in a Super King Latex Fusion 4 mattress. However, I would prefer a 2 mattress zip and link version to 1 super king mattress.

    Please advise as to whether a 2 mattress zip and link version is available, as I can not see this option on the website.

    If not available, please could you explain why this is, as I see that you do zip and link sprung mattresses.

    Many thanks,


    Hi John,

    The reason you won’t find many solid core zip and link mattresses, if any, is that the stretch material that such a mattress necessitates doesn’t lend itself well to being zipped together. The zips required for a zip and link are really heavy duty and the stretch fabric simply can’t take the stress of this as they need to move and flex far more than a traditional mattress which has edge support. Latex mattresses don’t have edge support as they are a consistent piece of latex, Adding edge support would compromise the over all comfort of the mattress and is necessary given the fantastic support properties of natural latex.

    We can do a bespoke order of two singles and a matching topper to give the appearance of a zip and link bed, or two singles and single toppers that can be pushed together. Given how heavy latex mattresses are there is minimal movement with them, this maybe the best compromise.

    Hope that helps. Lee

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