Hi color23,
If you are considering ordering from Foambymail (AKA FBM or Foam Factory and other names as well) then I would read this post and this post and this topic (about their polyfoam and sources) and this post (presumably from a past employee) before buying anything or considering them as a reliable supplier that provides accurate information about their foam products.
Unfortunately it’s not possible to make any specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first “rule” of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for you in terms of “comfort”, firmness, or PPP (Posture and alignment, Pressure relief, and your Personal preferences) or how a mattress will “feel” to you or compare to another mattress based on specs (either yours or a mattress), sleeping positions, health conditions, or “theory at a distance” that can possibly be more accurate than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
If you are attracted to the idea of designing and building your own DIY mattress out of separate components and a separate cover then the first place I would start is by reading option 3 in post #15 here and the posts it links to (and option #1 and #2 as well) so that you have more realistic expectations and that you are comfortable with the learning curve, uncertainty, trial and error, or in some cases the higher costs that may be involved in the DIY process. While it can certainly be a rewarding project … the best approach to a DIY mattress is a “spirit of adventure” where what you learn and the satisfaction that comes from the process itself is more important than any cost savings you may realize (which may or may not happen).
If you decide to take on the challenge then I would either use the specs (if they are available) of a mattress that you have tested and confirmed is a good match for you in terms of PPP as a reference point or blueprint and try and “match” every layer and component in your reference mattress as closely as possible or use a “bottom up” approach (see post #2 here).
There is also more about primary or “deep” support and secondary or “surface” support and their relationship to firmness and pressure relief and the “roles” of different layers in a mattress in post #2 here and in post #4 here that may also be helpful in clarifying the difference between “support” and “pressure relief” and “feel” that may be useful as well.
There is more information in post #9 here about the different ways that one mattress can “match” or “approximate” another one. Every layer and component in a mattress (including the cover and any quilting materials) will affect the feel and performance of every other layer and component and the mattress “as a whole” so unless you are able to find another mattress that uses exactly the same type of materials, components, cover, layer thicknesses, layer firmnesses, and overall design (which would be very unlikely) then there really isn’t a way to match one mattress to another one in terms of “comfort”, firmness, and PPP based on the specifications of the mattresses (even assuming that you can find out all the specifications you would need for both mattresses you are comparing).
I would also keep in mind that there are also no “standard” definitions or consensus of opinions for firmness ratings and different manufacturers can rate their mattresses very differently than others so a mattress that one manufacturer rates as being a specific firmness could be rated very differently by another manufacturer. Different people can also have very different perceptions of firmness and softness compared to others as well and a mattress that feels firm for one person can feel like “medium” for someone else or even “soft” for someone else (or vice versa) depending on their body type, sleeping style, physiology, their frame of reference based on what they are used to, and their individual sensitivity and perceptions. There are also different types of firmness and softness that different people may be sensitive to that can affect how they “rate” a mattress as well (see post #15 here) so different people can also have very different opinions on how two mattresses compare in terms of firmness and and some people may rate one mattress as being firmer than another and someone else may rate them the other way around. This is all relative and very subjective and is as much an art as a science.
The components in the Reverie mattresses and their design are unique to Reverie so the only reliable way to know for certain how one of their mattresses will compare to another mattress that has very different components and layers in terms of how they “feel” or in terms of firmness or PPP would be based on your own careful side by side testing or actual sleeping experience on both of them.
Yes … I would suggest a dedicated mattress cover that is specifically designed and fitted and is the correct thickness to be used with your mattress rather than a waterproof encasement which is a completely different component that is meant for completely different purpose (see post #6 here).
Density is a measurement of weight per unit volume and in this case is the number of pounds that a square foot of the latex weighs. When you are comparing the same type and blend of latex then firmer latex cores will have a higher density than softer latex cores but if you are comparing different types and blends of latex then the same density can have a different ILD (Talalay for example will have a different density than Dunlop in the same ILD and synthetic latex or synthetic blends will have a lower density than natural latex in the same ILD).
Again … every layer and component in a mattress (including the cover) will have an effect on the feel and performance of every other layer and component above and below it and specs such as ILD are only one of several variables or “specs” that will determine how soft or firm an individual layer or a mattress “as a whole” will feel to different people (see post #4 here). In addition to this the ILD of different materials or different types and blends of latex also aren’t always directly comparable to each other (see post #6 here) so using the ILD or other specifications of a particular layer or combination of layers as a reliable indication of how any mattress will “feel” or how firm it will feel to you compared to another mattress with a different combination of layers can be more misleading than helpful.
If both of the Dunlop layers you are looking at are 100% natural Dunlop then they would each have a different density if they are a different firmness (which is one of the ways that the information that FBM provides is unreliable). You can get a sense of how the density of 100% natural Dunlop relates to ILD in post #2 here and if both layers really are 100% natural Dunlop and really are 5.6 lb density then they would both probably be somewhere in the range of 39 - 44 ILD…
Latex is quite “sticky” and if you have unglued layers that are enclosed by a tight fitting cover that is suitable for your mattress then they are unlikely to shift in normal use.
Phoenix
Looks like I will have lots of links to check out tomorrow!