We ordered and paid for a talalay mattress, differential contruction consisting of an 8" 44 ild base with a 3" 19ILD comfort layer.
Without rehashing everything, the bed delivered ended up being 44 ILD with a 28 ILD comfort layer. The second comfort layer was delivered and it was a 4" 21 ILD comfort layer. neither of these two configurations were beds we had even tried.
In previous comments to me you mentioned that a 4" 21ILD would be “softer” than a 3" 19 ILD. I am a little confused about this. I know the thickness plays a role filling gaps…but lying on the showroom bed which had 3" of 19 ILD I felt my body sink in a little more-I felt more cradled and felt less pressure on my shoulder. On the current 4" 21 ILD I don’t feel I sink in as much…it feels firmer, not softer.
Is there something I am not understanding?
Also, I notice that the layer we were told was a 4" layer is actually 2 x 2"…is that normal nomenclature?
Assuming that everything else is equal (the same layers below it, the same material, the same ILD or softness level, and the same cover) … thicker layers of the same ILD will be softer than thinner layers.
The reason for this is that foam materials get firmer as you compress them to a greater percentage of their thickness until they reach maximum compression so a thinner layer will compress more than a thicker layer and feel firmer.
If you have a 2’ layer of a specific material on the floor it would be easy to imagine that it would be fairly firm because it would compress to a large percentage of its thickness and you would feel more of the floor underneath it. If you used 8" of the same material it would only compress to a much smaller percentage of its total thickness and you wouldn’t feel the floor underneath it at all.
Of course all the layers in a mattress all compress to different degrees simultaneously so how any layer feel always depends on the rest of the mattress and what is over or under it but if everything else is the same then thicker = softer.
If something is different between them such as having a mattress pad on your mattress at home that wasn’t on the mattress in the showroom then something like this could also account for the difference.
Yes this is very common because many manufacturers will keep 2" layers in stock and then use two layers if they want a thicker comfort layer. If the layers are glued together and are the same ILD then the glued layer would feel virtually identical to a single 4" layer. Of course if each layer is a different ILD or only one is the same then the 4" layer would feel different. If the layers are unglued then two 2" layers would feel slightly softer than a single 4" layer because each layer can respond a little more independently.
Many people have had the experience of testing a mattress in the morning and then leaving to test other mattresses and when they go back again to test the same mattresses they feel completely different because their context has changed. If two mattresses that are otherwise identical except that one uses a 4" comfort layer and another uses a 3" comfort layer … then if the thinner comfort layer feels softer it would normally be either the nature of subjective memory over time which is usually not particularly accurate (side by side comparisons in real time would be much more accurate), unexplainable differences in individual perceptions vs what most people would feel, or it could be because the materials in each mattress are different from what you think they are and aren’t the same ILD.