Hi csalinas.m26,
This is the type of “curiosity” that can end up turning “simplified choice mattresses” into “overwhelmingly complex choice” mattresses. The problem is that if a manufacturer provides this type of information to the 99% of their consumers that don’t understand that it’s basically meaningless it would only encourage them to believe that they can use the information to make comparisons between mattresses when they can’t.
The ILD ranges of the synthetic continuous pour latex that Casper uses in the top 1.5" of the mattress doesn’t correspond to the ILD ranges of other types and blends of latex so it can’t be used to make meaningful comparisons with other types and blends of latex or even other layers of the same latex that are a different thickness.
The IFD/ILD of memory foam is also very misleading because IFD testing produces different results for memory foam than it does for other more resilient materials and the IFD of memory foam also changes with temperature, humidity, and the length of time the memory foam is continuously compressed. The firmness/softness of memory foam will also vary with the specifics of the chemical formulation for the memory foam that affect its temperature sensitivity and its response time not to mention the thickness of the memory foam layer and the type and thickness of the layers above it.
The polyfoam base layer would be in a firmer range but how much the IFD of the polyfoam base layer affects the “feel” and firmness of the mattress as a whole will greatly depend on the type and thickness of the layers above it. A “typical” IFD for a base layer would be somewhere in the range of 28 - 32 but it could be softer or firmer depending on the design goals of the mattress. I would also keep in mind that IFD testing on polyfoam uses a 4" layer of foam while ILD testing on latex is generally done on a 6" core of latex so once again the ILD/IFD testing will produce different results (Polyfoam IFD’s are generally firmer than the same ILD with latex).
If I was a manufacturer or retailer in most cases I probably wouldn’t provide this information to my customers because most manufacturers or retailers would be well aware that if they do provide it to their customers the temptation would be too great to try and use it for making comparisons and any knowledgeable retailer or manufacturer would realize that this would be much more misleading than helpful and their customers would probably end up choosing a mattress for all the wrong reasons.
While I don’t know the ILD/IFD of all the foam layers in the Casper … a quick phone call would be the most reliable source for this type of information if they provide it to their customers.
Phoenix