Comparing ILD of natural vs blended latex, and ILD of layers vs single piece

After only a little testing, I quickly decided I preferred the feeling of latex over memory foam. The mattress I liked the best was at The Natural Mattress Store and was the Awareness model in “Soft”. It took several phone calls today to various stores in that chain to get the information I needed. The first call was to the actual store I was in yesterday and the salesman was less than helpful or knowledgeable. He actually told me there was no such thing as blending synthetic and natural latex, and that any “blended latex” meant it was blended with polyurethane foam :S Fortunately, I was able to get in touch with very helpful people on the third and fourth stores that I called, and they were able to provide me with the technical details of the mattress that I liked. Because of my experience with the first store, I was initially put off by the company, but after speaking with the others I was very pleased. Unfortunately, even taking into account that it is worth a small premium for buying local, their products are overpriced and outside of my budget. They definitely push the organic angle, which I don’t buy into.

I am still not sure if a 100% latex mattress is in the budget, so I want to shop around and see what it would cost to duplicate this mattress.

The Awareness line mattresses is made from three 3" layers of all natural latex (not glued), covered in a zippered organic cotton cover with quilted organic wool. The “Soft” version contains the following:

Top layer: 3" Talalay in ILD 20-24 (Soft)
Middle layer: 3" Dunlop in ILD 25-30 (Medium)
Bottom layer: 3" Dunlop in ILD 40-49 (Extra Firm)

I think I would prefer the top layer to be a blended Talalay, for price concerns as well as the slight benefits in durability since it is a lower ILD. My question is, will a 3" thick piece of blended Talalay like Talatech (60/40) in ILD 20-24 feel the same as the 3" piece of natural Talalay in the same ILD?

A second question revolves around the bottom two layers. From searching the forum, I know that two 3" pieces of latex in a particular ILD will feel softer than a single 6" piece of latex in the same ILD. With that theory in mind, if I wanted to combine the middle layer and bottom layer listed above into a single 6" layer (if that was my only option with a particular manufacturer), would the layered medium over extra firm feel closest to a single medium-firm layer (ILD 35-40)?

And am I correct in assuming that if my budget forced me to go with a poly-foam core, that I should just throw out the window the idea that I want my top layer to be Talalay in ILD 20-24? Because there is no way to compare how it would feel over the poly-foam core versus the latex core?

Also, as I sit here and write this out, I wonder why I just can’t order a zippered mattress cover and the three pieces of latex. I’ve seen Phoenix advise against constructing your own mattress before, but I’m not sure what my concerns should be in this scenario where I know the components and layering. It seems to me that the feeling of the different covers would be my biggest (only?) issue. Of course that’s assuming it would be cheaper to do myself, which I do not know if that is the case yet.

Hi ehuesman,

That’s unfortunate. They certainly aren’t doing themselves any favors by having salespeople with so little knowledge. Fortunately this is more the exception with most local manufacturers.

Unfortunately … “organic” can sometimes be a “marketing code” for expensive. I tend to share your sentiments overall (although organic is more important to some than to others) and you can see some of my thoughts about “organic” it as it pertains to latex in post #6 here.

Post #4 here has more about trying to duplicate another mattress and the reasons why it can be very difficult to do more than “approximate” it. It’s usually best to “rate” each mattress you test against a common set of criteria rather than using another mattress as your 'target".

ILD is only one of the measurements used to rate the softness of a mattress and it is usually best used to compare the same materials but having said that all natural Talalay will feel very similar to most people in a 3" layer to blended Talalay although some who are more sensitive may notice some difference between them because natural Talalay is a denser material which will get firmer a little faster than blended Talalay in the same ILD and an ILD measurement is only completely accurate if you happen to sink into a layer by exactly 25% (how ILD is usually measured).

I would keep in mind that this would be more true in separate comfort layers that are closer to the surface than it would be in deeper layers where the difference may be outside of most people’s perceptions.

Two layers with a different ILD will have a different compression modulus (a measurement of how quickly a layer or layers get firmer with deeper compression) than a single layer with a single ILD and compression modulus can have just as big an effect as ILD on how a material feels in real life. Other factors such as point elasticity and different compression curves between different materials can also play a role in how soft or firm they feel for different people. Having said that … the layers that are closer to you will be a more obvious part of how a mattress feels for most people so if a middle layer was the same as the upper half of a single layer it would be relatively close for most people (depending on weight and individual sensitivity to different “types” of softness) so if the medium firm layer was the same type of latex and had the same ILD or perhaps a little firmer than the medium middle layer over extra firm then it would probably be fairly close … but again not for all people. The closest would be to have two thinner layers which were the same ILD as the single layer.

The upper pressure relieving layers usually have a bigger effect on the apparent “comfort” of a mattress for most people so if the top layers were the same and were in the range of 3" or so then for many people it would be a reasonable approximation. This would also depend on how heavy they were which will change how much of an effect the middle and even lower layers have on how a mattress feels and performs. Heavier people (or side sleepers) sink into a mattress more than lighter people or other sleeping positions so the lighter you are the more likely that they would “approximate” each other in terms of “feel” although they may still be quite different in terms of performance in ways that aren’t as readily apparent (such as alignment and how they respond to changes in position). You can read a little more about the difference between a latex/polyfoam hybrid and an all latex mattress in post #2 here.

Post #15 here has more of my thoughts about this and while a component mattress can be a good idea if you are working with a manufacturer that has the knowledge and experience to give you some guidance and offers layer exchanges and materials and components that are known to perform well together … I would discourage trying to do it on your own in most cases because mistakes can be costly both financially and in terms of sleeping quality. I have seen too many people end up with mattresses that just don’t work the way they want them to when they try to become their own mattress designer or when they try to make changes without really knowing what change will have what effect they are looking for and without really having the knowledge and experience to build their own mattress successfully. It may also not be significantly less compared to some of the value in component mattresses that are available.

While I understand that cost is an important part of value and sometimes doing everything yourself can also be worth it for some people just for the challenge, “fun” and learning experience alone … years down the road you will remember much more about how well you slept on a mattress and on how suitable it was for you than you will about relatively small differences in price IMO.

Phoenix

Thanks for you reply Phoenix. At least I know I am on the right track with my research - I’d already read all the links you directed me too, some of them a couple of times!

This makes perfect sense, BUT I am not trying to design my own mattress, I am simply trying to be a cheat and copy a mattress that is out of my price range. I still don’t know if it would make financial sense, or if it is even possible (from the availability of materials perspective).

With that still in mind, is latex foam always designated as an ILD range? The Talalay soft had a range of 5 (20-24), the Dunlop medium had a range of 6 (35-40), and the Dunlop extra firm had a range of 10 (40-49). I would think if two mattresses had the layers on opposite ends of the range (a 20/35/40 versus a 24/40/49) that they would feel significantly different, even though they would be considered the same mattress. No?

I do understand that Dunlop “settles” during the manufacturing process and thus the bottom may have a different ILD than the top. But is a range of 10 (like on the extra firm) normal?

you can easily buy poly foam in any ILD from about 10 to 90, which is twice the range that you need for a mattress. you can also get poly foam in both standard, HD and HR grades rather easily.

as for Latex - Brooklyn Beddding sells 2" and 3" toppers in every ILD from 14 to 44 which is also all the range most anybody needs. i have their 19 ILD topper and it sort of feels like the ILD is about right. i should be getting their 36 ILD topper on Friday and i’m keeping my fingers crossed that it is actually 36 ILD because you don’t order by ILD there but by a different scale - so there is a possibility of things going wrong there - let’s wait and see.

i also suggest you don’t dismiss memory foam so fast. after trying latex for the first time my initial reaction was same as yours - to hell with memory foam ! but initial reactions aren’t very useful with mattresses. many people on this forum who have purchased latex mattresses have complained of latex mattresses being “too bouncy” which i thought was funny because you have to expect that when you buy latex …

however just because in a showroom the bouncy feel may be fun and seem like a good idea you may not feel about it the same way when you sleep.

you might consider latex / memory foam hybrid mattress - brooklyn bedding sells one. unfortunately i don’t know if you would be able to try such a hybrid mattress out - ultimately this approach may be the biggest gamble of all since you would have to be going entirely off your imagination, not knowing what the end result will feel like.

even so - a hybrid memory foam / latex is what i want.

brooklyn bedding model uses 3" of memory foam over 3" of latex over 7 inches of poly foam - this is potentially very clever - but then, that’s just in theory.

humans tend to think in binary terms - yes or no - black or white - memory foam or latex - which is why from marketing perspective a hybrid mattress may be hard to sell, but they do exist. there is also one very popular model on Amazon but it only uses 2 inches of latex under a ton of memory foam and many complain it is too soft.

g1981c,

Thanks for your reply.

Ironically, memory foam over latex core was the only model one of local manufacturers had on display and was the first bed I tried out yesterday. While it wasn’t uncomfortable by any means, I decided I just didn’t like the inherent feel of memory foam. My wife actually says it gives her a sort of motion sickness because she feels herself slowly sinking in. That part doesn’t really bother me, but I like the “push back” and faster response of the latex, especially when changing positions. I’m also not completely sold on the idea that the industry has solved the sleeping warm issue, which is a concern for me since I already naturally sleep hot.

as far as doing the mattress yourself i have to agree with what Phoenix told me earlier - it is not worth it unless you want to enjoy the process itself

i’m building a mattress right now and it’s really a lot of hassle - more than i imagined - if you are ordering several foam pieces from different suppliers ( as i am ) chances are one of them will mess up and hold your process up for weeks. then other layers you buy may end up feeling different from what you expected. and the entire time you’re thinking how will this layer feel with that layer and you can’t think of anything else because your head is full of mattress … for weeks and weeks because that last supplier is still holding you up.

so basically if you want to be challenged, and you enjoy designing and building things and doing tons and tons of research, and your back is in pretty decent shape and you don’t mind the hassle and aggravation then yes - it can be worth it. on the other hand if you simply want to save money then i think you stand more to lose, than you do to gain.

personally i was a DIYer since high school. i built speakers and subwoofers, which involved a lot of theoretical knowledge as well as manual labor. it was a lot of fun and the results were respectable but also a lot of money time and effort went into it. ultimately i never realized the savings i thought i would because as much knowledge as i had it was never quite enough so while my designs worked they were never as cost efficient ( price / performance ) as good commercial designs, and in the end the only thing that made it worth it was enjoying the process itself and the bragging rights that come with building something yourself.

i’m halfway through my mattress build now but i can already tell it’s going to work out abou the same way as my speaker building efforts back in high school and college.

Hi g1981c,

If you know the type of latex you have tested (Dunlop or Talalay … blended or all natural) … the ILD (which sometimes isn’t available or specific) … and the specifics of the cover and all the same materials are available to you (and described correctly by your source) … then you would be able to come pretty close. Sometimes the difficulty though is if you need to exchange a layer because most suppliers either don’t allow returns or there are costs involved and if you reach a point where re-arranging layers is not enough and you need to exchange one … then you may not have access to the help you may need to make the best fine tuning adjustments because what to change can sometimes be counterintuitive. If you know the specs of the mattress you are trying to duplicate and if all the materials and components are available and you get it right the first time … then it can certainly save you some money (depending on your supplier and on which component mattress you are comparing it to) … there’s just a greater risk involved in matching the layers and in exchanging them if you need to.

Some types of latex are more specific and some are not. Blended Talalay for example comes in “single” ILD ratings from low teens to mid 40’s as you can see here while others are more of a range. All natural talalay from Latex International comes in N1 - N5 and you can see the ILD range of each one here). Most Dunlop also has a wider range of ILD’s across the surface of a layer because it is not as consistent as Talalay and some Dunlop manufacturers don’t even provide an ILD and only sell their latex with density ratings (density is directly related to firmness in latex). In many cases … retailers will “guess” at the equivalent ILD range of a certain density of Dunlop but I have seen many of them be way out in their estimates.

You can read a little more about latex ILD’s in post #6 here and some Dunlop ILD estimates based on density in post #4 here.

I think that if the types of latex were identical that they would certainly feel different but an ILD difference of 4 or so is not a lot and the top layer would be the biggest contributor to the feel of the mattress although depending on body type, sleeping positions, and individual perceptions … slightly firmer comfort layer and the slightly firmer middle transition layer would make the second mattress noticeably firmer for most people. The lower layer would have the least effect on the “feel” although the second one would certainly provide better support for most people as well because of the fairly big jump in ILD. Again … this is assuming that the type of latex is the same between them because once you look at different types of latex then ILD alone is not as reliable a way to compare them.

Phoenix

I lack the imagination for design, but other than that, this pretty much describes me. Especially the research part, my wife already thinks I have “gone down the rabbit hole” in regards to mattresses. She is probably right, which if I’m completely honest, comes into play in me deciding on latex. I believe in what I’ve researched in regards to durability, and I enjoyed how it felt. I don’t want to leave other options open because that multiplies the amount of research needed.

Now I just need to find out how to get what I want for a price I can afford!

yes memory foam has “creep” which Phoenix for example also doesn’t like. well you know better what you like, all i was saying is not to rush to judgement but to take the time to do more realistic testing - the kind which is most like real sleep. in other words instead of hopping on and off mattresses from one to another, as most people do in the store, you would have to lay down on a single mattress for an extended period of time and try to relax the same way you do as when you actually go to sleep and focus on what you feel THEN. Phoenix has articles on here on how to properly test mattresses, which i think may be the most important information on this entire site - because ultimately it is not your job to design mattresses, but it IS your job to test them.

as for sleeping hot yes - foam is what is used to insulate buildings, and mattresses are many times thicker than such foam so it can certainly be a problem. it is so bad that i actually saw a product that uses water loops, a pump, a fan, and a solid state thermoelectric cooler and costs about $800 just to keep you cooler in bed ! in any case i would never consider sleeping directly on foam - that’s just disgusting IMO lol. i always had some kind of batting between me and the foam - the problem is with memory foam any type of thick topper or even pad on top of it will change its feeling partially defeating the point.

the reason i’m still probably going to go with memory foam in the top layer though is density. latex density varies with firmness such that while firm latexes have high densities in the 5 LB range, the softer layers of 20 ILD and less can have density as low as about 3 LB. i have developed a theory ( which is just that - a theory, but i’m going with it ) that density has direct effect on pressure relieving qualities of foam REGARDLESS OF TYPE OF FOAM. now i want to be very clear IT IS JUST A THEORY OF MINE and i am not in any way trying to represent this as fact ! but i believe this - and based on that, a 8LB memory foam or even 5LB memory foam i think will be better than an equally soft latex which will be around 3LB density.

so most likely i will be using a thin 2" layer of 8LB or 5LB memory foam on top of many inches of latex ( which have already shipped ). i have yet to order the memory foam because i need to obtain samples of it first to decide which one to use.

Thanks again for the reply Phoenix.

I see now how it could be more difficult than it appears to “duplicate” the mattress I tested (unfortunately). Especially if The Natural Mattress Store is guessing at the ILD of the the two bottom layers, which are both Dunlop. I think the top layer is easy, they told me it was sourced from Latex International and that the ILD was 20-24. Since all of the latex used by The Natural Mattress Store is 100% natural, then that means the top layer was the N2. But figuring out those Dunlop layers might be a crap shoot.

I didn’t ask where the Dunlop was sourced, is it likely that it comes from Latex Intl also? I didn’t really see that on their site.

I guess I’m back to square 2 (at least I still know I want latex).

yes i remember a person on this site has attempted to duplicate pure latex bliss - in fact he asked a local mattress maker to do it for him - and the result didn’t feel very similar. there were also people who bought the real pure latex bliss and said it didn’t feel like the one in the store.

so if you are planning to get it right on first try by simply ordering all the layers and putting them together at once i think more likely than not the end result will not feel the way you expect it to.

that’s why instead of using 2 or 3 thick layers i am using multiple 2" and 3" layers and i’m not ordering all of them at the same time. i have ordered about half of them, and based on how they feel i will order the remaining layers to try and compensate for the mistakes i made with the first few layers.

even so this is far from foolproof because sometimes the layers interact in strange ways …

for example my 19 ILD topper feels way too soft by itself but with a few layers of farbric on top of it it feels firm.

and just yesterday i received 50 ILD HD PU foam, so to test it i tossed it on an old spring mattress i have and incredibly - the additional 3 inches of foam on top of a rather firm spring mattress made it twice as firm as it already was ! yes 50 ILD foam is very firm, but i thought that adding 3 extra inches of foam on top can only make the overall structure more cushy because instead of 8 inches of padding now there is 11 - but i was dead wrong - instead of softening it became twice as firm.

so even if you’re ordering one layer at a time you can still mess up in the end because when you put the layers together they may interact in ways you didn’t expect.

brooklyn bedding on their page advertises that you can exchange the topper for a different ILD at no charge - which was obviously a selling point for me - however when i called them they said that what they meant is that they exchange top layer in a mattress, not a topper - they said however that they would still exchange my topper if i wanted.

but even with the ability to exchange it for different ILD it is still not foolproof - because it comes in a cover that you can’t remove if you want to be able to exchange it, and the cover will affect the feel of it. plus you have to pay return shipping on the topper and because you can’t vacuum seal it as vendors do it can get expensive due to dimensions.

Sounds like you have your work cut out for you g1981c, lol.

I’m back to wondering what is so bad about trying to duplicate a mattress. Isn’t that what we are trying to do anytime we buy one online without having tried that exact model beforehand? We go out to local places and test different mattresses to see what we like, then we find an online retailer that makes something similar right?

Maybe I’m wrong on that, maybe I’m supposed to be calling online retailers and telling them what I liked, and asking what they have that feels like that local mattress, not necessarily constructed like that local mattress. Of course, then we have the problem that the online retailer doesn’t have access to that local mattress (99% of the time) to feel it, not too mention the feeling of a mattress is highly subjective and the online retailer might think it feels differently than I do.

So if trying to duplicate a mattress where I reasonably know the components in the construction is a bad idea, how could I ever purchase a mattress without having tested the exact model?

I know it seems like I’m trying to talk someone into supporting the idea of me putting a mattress together myself, but that is not it at all. I’m just not sure what else to do since local manufacturers are waaay outside my budget.

Hi g1981c,

This would be like saying “I have a theory that the sun orbits around the earth” or “I have a theory that heavier foods are healthier than lighter ones” where you could find empirical arguments that support it based on appearance even though the fundamental basis of the “theory” is wrong. You will find higher some higher density foams that are more pressure relieving than some lower density foams but like anything else including your speaker projects … single “specs” by themselves without taking into account all the other factors that are interrelated usually don’t work out so well. The main “specs” of foam material that affects pressure relief are it’s ILD, compression modulus, and point elasticity (the ability to take on the shape of the body). With polyfoam formulations … density has nothing to do with ILD or point elasticity although it is connected with compression modulus. With memory foam density is connected with compression modulus and point elasticity but ILD is meaningless in memory foam except as a very inaccurate comparison between memory foams only. There are also other factors with memory foam that will affect it’s performance and it’s ability to relieve pressure. ILD is also measured after a waiting period at the bottom of a compression testing cycle and during this waiting period the force required to keep memory foam compressed becomes lower as the foam relaxes while with more elastic and resilient foams the force required to keep them compressed is fairly steady.

I don’t either like or dislike foam creep … it’s just part of the properties of a foam that need to be taken into account when you use them. It would be like damping or attenuation of certain frequencies … it’s just one factor in design and in excess it can increase the risk that a particular design won’t be successful in achieving its design goals (which is the case of a mattress is the balance between pressure relief, posture and alignment, and personal preferences).

Phoenix

Hi ehuesman,

If their latex comes from Latex International the it would be N2 yes.

If a Dunlop layer has even been tested for ILD accurately then it would give a reasonable indication of the ILD range for that piece (keeping in mind that ILD with Dunlop has several variables even with the same foam core) but density is also a good way to compare the firmness of Dunlop because all Dunlop manufacturers will describe their foam by density even if they don’t by ILD and if the foam is 100% natural then density comparisons between different manufacturers will be fairly close.

Most of the latex from Latex International is Talalay and they don’t have any 100% natural Dunlop. If it’s 100% natural Dunlop it could come from many companies including Latex Green, Arpico, Latexco, CoCo latex, GommaGomma, or one of many other Dunlop manufacturers around the world that make some good quality Dunlop latex.

I don’t think that trying to duplicate another mattress based on specs is “bad” at all … I think it’s just important to have reasonable and realistic expectations about the likelihood of success (or accuracy) because most people have little idea about how difficult it may be to duplicate another mattress. It also depends on whether you are trying to duplicate just the “feel”, the design, the quality of materials, or all three. Post #2 here also has more about trying to duplicate another mattress. The limiting factors in success are the ability to get accurate information about the mattresses you test in the first place (so you know what materials you are duplicating) and your ability to find the exact same foam in the same thickness at various suppliers and your ability to also match any other design differences in the mattress (construction method, covers, quilting etc). Every difference between your mattress and what you are trying to duplicate can make a difference in how it feels and performs … sometimes in surprising ways for those that aren’t used to working with mattress materials, foams, and components.

Mattress design is about a “conflict” between the need for pressure relief which requires “softness” in the upper layers and the need for support/alignment which requires “firmness” in the deeper layers and the choice of preferences which may require what someone has become “used to” or “likes” (just like food preferences for sweets or starchy foods that have developed over time that may or may not be healthy for someone) and mattress design and theory can often be counterintuitive and surprisingly difficult. Like chess or golf or other lifetime endeavors where the learning curve never ends … people who make mattresses will tell you that there are so many variables between people and mattresses and material combinatioins that they will probably never “master” it … although some are certainly better than others.

Sometimes differences can “cancel each other out” in the case of two mattresses that have different designs that feel and perform in similar ways for someone and sometimes small differences can have a compounding effect and make each one feel much more obvious than it would be on its own.

What you test locally is a guideline that can certainly be helpful but as you mentioned … because of differences in design and in subjective vs objective perceptions … it can usually only be used as one indication of a mattress that may work best for you. Every “piece of information” that you include in your discussion with a manufacturer or retailer increases your odds of success within the limitations of the options they have available. The upper half of a mattress will also contribute more to the “feel” of the mattress for most people than the lower half so this can also be especially useful to know both in the “target” mattress and in the one you are purchasing.

With an online order though … there is always risk involved to different degrees depending on mattress return and exchange policies, design flexibility, and other factors which IMO should be realistically taken into account as part of someone’s “value equation” rather than “minimized” as being irrelevant or “not likely to happen to me”. To the degree that what you order online is different from what you tested … sometimes in even seemingly smaller details (and assuming that your testing was careful and objective and a reliable indicator of your long term experience in the first place) … then “educated guesswork” or calculated risk" is what your choice will boil down to. It’s important to make sure that you have asked yourself “what is my recourse if I guess wrong” and that you realize that this is all about shifting odds in your favor as much as possible. Sometimes you will “win” and sometimes you will “lose” and what can happen if you lose (make a wrong choice in terms of pressure relief, support, or "feel) and the odds of that happening is what needs to be realistically taken into account.

Online manufacturers make great quality and value available for those areas of the country where they aren’t as widely available (or available at all) locally. If you happen to be in one of those areas … then it’s really a matter of weighing out the pros and cons of local vs online and if you do decide to go in an online direction … then shifting the odds in your favor as much as possible … all the while realizing that your odds will never be 100%. In realistic terms … if a mattress in its “final configuration” (after the initial break in period and after any adjustments, fine tuning, layer rearranging and layer exchanging) is 90% of your “ideal” in terms of all your needs and preferences in both the short and long term … then this would be my “definition” of being a great success and is much more than what the large majority of people will realistically achieve in the larger consumer market.

Phoenix