Mattress Forum

I would also not buy anything from FBM (or any of their other dozen or so websites) for the critical upper layers of a mattress. Foamorder is not one of these websites and is a separate company. You just never know what you will receive from FBM both in the type of latex (Dunlop or Talalay) and more importantly the ILD of what they send you. If it ends up being wrong then you have absolutely no reference point to help you know where to to from there.

A layer that is 2.8 inches is often called 3" but it is a full core cut in half. Cores usually vary by manufacturer and type of latex between 5.5" and 6".

I believe that the Flobeds video concerning Dunlop is completely misleading regarding the durability and longevity of Dunlop.

So I believe your option #1 is a decent first step although the 3" of latex may need just a "little" more for your side sleeping depending on what is under it ... alhough it sounds like you like sleeping on "wood" (laughing) so it may be fine for you.

The next "step" I would probably take once you know the thickness and ILD of the comfort layers you need ... and it you want to "build up" to more latex would be to add more latex in a middle layer over firm poly (not 6" by itself) but I really believe you need to comfirm what thickness and ILD comfort layer works for you first.

Phoenix

PS: (added after) Here is a reference point for a 6" good quality poly with 3" of Talalay over it mattress in terms of pricing http://www.walmart.com/ip/EcoSleep-sup-TM-sup-10-Cool-Align-Talalay-Latex-Mattress/13431007.

I do know about history of FBM and was willing to risk trying their 3" given my budget.  But I am looking now at foamorder since I can get some good deals on 3" clearance dunlop.  

The reason I mentioned the ILD's that I did for comfort layers is that it seems inline with what lot of other people have, maybe I am wrong.  For example...I took flobed test and it says to have firm over xfirm over xfirm and their firm is 32 ILD.  Also on savvyrest site they say a lot of customers get medium over firm and according to what someone posted on here it sounds like their levels range as soft = 30 ILD and med=35 and firm=40.  

Minneapolis is about 2 hour away so hopefully I can get better idea trying out mattresses and that the salespeople are able to tell me what the ILD's are for the mattresses.  

The first is to form enough of a cradle around your sleeping profile that the pressure is spread out over your body enough to relieve pressure ... especially in your "most difficult" sleeping position (on your side). This is the function of a comfort layer. The more "gaps" there are to fill in ... the deeper this cradle needs to be. Side sleeping has the biggest "gaps" to fill in so in general terms it needs a thicker softer layer than other sleeping positions to relieve pressure. How deep a cradle you need or how thick and soft the top layer needs to be is also dependent on how sensitive you are to pressure. There aren't very many people who side sleep on a mattress with 32ILD Dunlop in the comfort layer and find it comfortable. Flobeds has a 2" soft convoluted topper on all their mattresses for this reason (that doesn't show up in the "firmness selector"). Any kind of "general" guideline like these are also notoriously unreliable. The Savvy rest site also recommends softer latex for side sleeping and certainly not in the ILD's you are mentioning http://www.savvyrest.com/blog/exploring-ild. This part in other words is about how deeply you sink "in" the comfort layers.

The second function is to keep your spine in alignment in all your sleeping positions. You need a mattress that will stop you from sinking "down" too far in your heavier parts (like your hips) and will also "hold up" the gaps (like your waist or the small of your back) so your spine stays in it's natural alignment while you sleep. This is the role of the deeper layers of a mattress. They are designed in other words to "hold up" the parts of you that need holding up while allowing the comfort layers to form the cradle you need.

The middle layers play a dual role. In a 9" mattress for example, it is quite possible that you need a thicker comfort layer than 3". This means that the top part of the middle layer is part of what helps to form your cradle. If it has an ILD of say 28, then the very top part of it would be softer (as explained on the Savvy rest site). As you sink in deeper it acts as part of your support layer and helps stop the sinking down. If you chose a very firm middle layer and your top layer wasn't thick enough to form enough of a cradle for you, then it would only help hold you up and could contribute to pressure problems.

In my own case for example (6'5" 195 lbs) ... 3 one inch layers of soft latex over a firm layer creates too much pressure for me. A single 3" layer of around 22 is right on the edge. It does the same for my "curvier" other half who is 5'7" and about 130. Sleeping directly on anything over 24 ILD Talalay would also create pressure problems for both of us and for many others as well.

Using layering that gradually increases from softer on top to firmer on bottom is what I have called a "progressive" approach. This uses the top 3" and part of the middle layer for comfort and uses the deeper part of the middle layer and the bottom layer for support.

Using layering that has a thicker top comfort layer that doesn't need any "help" from the middle layer for comfort and then using firmer middle and bottom layers is what I have called a "differential" approach. If you search these two terms you will find a lot of posts that go into each.

If you were "typical" (if there is such a thing) for your weight and sleeping position you would need around 3-4" of softer talalay (around 24 or less) on the top and then firmer on the bottom as there is more weight to hold up. Your preferences and of course your sensitivity to pressure issues can lead to a wide variance here.

A 3" layer that was soft enough (I really have my doubts that any of the Dunlop ILD's you mentioned would be) over your 5" of 40 ILD poly may be enough but if you "go through" the 3" softer latex and "hit"  the really firm layer underneath then you may be uncomfortable and firm layer under may still cause pressure issues even though it would be great for support. A mattress that is too firm (doesn't let you sink down enough to create good spinal alignment) and a mattress that is too soft (lets you sink down too far called "hammocking) would both offer poor support (poor spinal alignment).

Your 6" "old" poly may work better for helping with pressure but may not hold you up as well. I suspect that it may "help" enough with your comfort though that it may work better but I don't know it's ILD or how it is currently "performing".

Again in "general" terms ... I wouldn't go with anything less than about 8" (with certain exceptions such as possibly a single slab of softer Dunlop or other foam that has a very high compression modulus) since you would likely need this much not because less wouldn't support you but because you need the flexibility of different layering to provide both comfort and support in all your sleeping positions and less than this gives you less to work with. Unless you want to do additional research on compression modulus (also called sag factor which is another of the important qualities of foam that determines how well it works) I would stick with a minimum of 8" even though some of this can be firmer poly.

In any case ... I would do some "real world" testing to see if medium/firm Dunlop is really what you like to sleep directly on. It may work well for you but you would certainly be in a very small minority of side sleepers that didn't need something a little softer on top.

Phoenix

I wish I had more of a budget.  Originally I was looking at 3" latex, 3" premium 36ILD foam, and 3" lux 50 on bottom.  The reason I decided against the 36 foam was that I read couple people said it didn't last very long.  The only economical place I can find for quality poly is foamdistributing.  

I think that 3" is sort of a "starting point" to go up or down from. Some will prefer 1" (stomach sleepers maybe) and some may need 5" (heavier side sleepers) but 3" is a good place to begin from.

Originally I was looking at 3" latex, 3" premium 36ILD foam, and 3" lux 50 on bottom.  The reason I decided against the 36 foam was that I read couple people said it didn't last very long.

How long a polyfoam lasts has very little to do with its ILD and much more to do with its density. Lower grades are up to 1.8 lbs/cu ft. Medium grades are called HD (High Density) and are from 1.8 - 2.4 lbs/cu ft. the highest grades are called HR (High Resilience) and are from 2.5 and up. Each of these can come in any ILD. The higher the grade (many people misrepresent their foam and call it something else), the longer it will last.

The only economical place I can find for quality poly is foamdistributing.

There are many places to buy polyfoam of any quality and density. Often local foam shops will carry then at good prices. A few of them are in reply #12 here but there are many more.

I might also try and see if I can send it a 1 square foot sample of the top poly I am sleeping on to Flobeds and see if they can give rough estimate of what ILD to latex it compares with  which would give me starting place on what I might like for latex.

A polyfoam ILD will compare roughly to the same ILD in latex. It won't feel the same because ILD is only "true" at 25% compression but it will be a rough comparison. Testing mattresses will be a better indicator than having anyone guess what your polyfoam may be but the ILD of poly you know you like is a good place to start.

Do you know of any posts or information where discussions have compared latex layers to approximate a certain big S mattress.  For example, I mentioned at local stores I liked the Simmons extra firm beautyrest....the salesman said they referred to it as the rock...but it felt fine to me.

There are quite a few threads like this but the information is a "side effect" of the topic. I don't know of any specific topics like this. If you know the construction of a poly over spring mattress that you like, then a good place to start is to use similar layering in latex except the spring would be replaced by very firm latex. Some people even have latex over springs and love it (many of the mattress surgery threads are like this and have great layering information in them). Some of the mattress surgery threads are in the "highlited threads" link. Some of them are still "experimenting" and still posting great feedback on the effects of changes they make.

 BTW, the 6" top poly I am sleeping on is an Englander all foam that is like 40 years old.  I checked and it is not latex.  When I started journey few years ago because of my bad back I tried building a cheap tempurpedic with the extra firm poly base and memory and didn't like it.  I foolishly got talked into an Englander coil plush by salesman and ended up selling it to someone couple months later.  Back then I really wanted to try latex and wish I pursued it more. 

If it really has lasted over 40 years of use ... it may be latex after all as there were a lot less polyfoam mattresses 40 years ago. Do you know for sure that it's not Dunlop latex? It would sure be unusual for any other type of foam to last that long but it's not so uncommon for latex to last that long.

In any case, wih a bit of research it's not too difficult to "duplicate" "S" brand mattresses to a large degree anyway with superior "ingredients" if you know it's construction and have tested out your preferences.

Phoenix

PS: A simmons extra firm beautyrest usually has 1.5 - 2" of soft polyfoam over an insulator layer over very firm springs. This would be "sort of roughly" equivalent to 44 ILD latex with 2" of 14 ILD talalay over it. I'm using this as an example ... not to give you "an exact duplicate". This would need to be tested to see if it worked for you. Some who really like the feeling of innersprings (even more than a latex core) with latex over it may use 2" of 14 ILD latex (or something maybe a bit firmer) over an insulator of some kind (very firm 1" foam?) over the springs. These are examples that could work for certain "S" brand preferences.

Mattress construction is both a "science" and an "art" but if you join the ranks of the "mattress underground" (you can search it if you're in the mood for a laugh) ... anything is possible (laughing).