Hi OverThinker,
The thickness of a mattress is just a side effect of the design and by itself isn’t particularly meaningful. The thickness of a mattress or of individual layers doesn’t necessarily make any mattress better or worse … it’s only one of the specs that affects the overall feel and performance of the mattress “as a whole”. There is more about the effect of thickness in post #14 here but regardless of how thick or thin a mattress may be … the most important part of the “value” of a mattress purchase is your testing and personal experience which will be the most reliable way to know whether a mattress “as a whole” is as suitable “match” for your body type, sleeping positions, and preferences in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences).
[quote]-Looking to keep cost down but will go to 8" if needed.
-I am mostly a side sleeper.
-Appoximately 180lb (haven’t been weighed for a few years so don’t really know) with a
little extra air in the spare tire.
The mattresses I tried were a single piece of soft and single piece of medium 3.0lb Qualux (by Carpenter?). I asked the salesman for the support factor but said he didn’t have it. Do you know if it is a high resilience foam? They have three firmness options available.
-Soft ILD 19-25
-Med ILD 34-40
-Firm ILD 41-46
I read that ILD changes with the thickness (makes sense when you look at how it’s measured) but salesman told me it doesn’t.[/quote]
Qualux is a “family” of polyfoams made by Carpenter with some “latex like” characteristics (see post #2 here) but there is also a wide range of quality/density available in the “family” and some of them (such as the Qualux ultra) meet the definition of high resiliency (2.5 lb density or higher, compression modulus of 2.5 or higher, and 60% resiliency) and some don’t.
Your testing will tell you whether a mattress that uses it is a good match for you in terms of PPP and the spec that I would be most concerned with is the density which is the single biggest factor in the durability of a foam material.
Mattress specs and “theory at a distance” can be useful as a starting point or for gaining some insights into how different layers and components interact with each other in many different ways but IMO it’s among the least effective ways to choose a mattress. In my experience … focusing on design or comfort specs (ILD, layer thickness or even more obscure specs like compression modulus etc) can be counterproductive without specific reference points based someone’s personal experience that can be used to to “translate” this type of information into something meaningful. In most cases it will just lead to “information overwhelm” or “paralysis by analysis” which can lead to choosing a mattress for all the wrong reasons. Too much information and too little information can both lead to choices that are less than ideal.
There is more about the most important parts of the “value” of a mattress in post #13 here that can help you make more meaningful comparisons between mattresses and the only specs you will need are the “quality/durability” specs that can help you identify whether there are any lower quality materials or “weak links” in the mattress.
The better options or possibilities I’m ware of in the Edmonton area (subject to the quality/value guidelines I linked) are listed in post #136 here which includes some comments about the retailers you have mentioned.
Phoenix