Converting U.S. foam density to European foam density

I have a high density urethane mattress purchased in the states with the following specs: base layer 2.8lb density and ILD of 45, top layer of 1.8 lb density and ILD of 18. Can anyone tell me what this might translate to in the european market, specifically spain?
Also, somewhere on this website is an article including a source for purchasing a cork (?) board to place underneath your mattress as a more breathable alternative to wood - but now I can’t find it. Navigation help appreciated if anyone recognizes this.

Hi parra,

Density specs can be converted from lbs/m3 into kg/m3 which is commonly used in Europe with the converter here.

2.8 lb/ft3 would be the equivalent of 44.85 kg/m3 and 1.8 lb/ft3 would be the equivalent of 28.83 kg/m3.

ILD (or IFD) is a “comfort spec” and is measured differently in different areas of the world and with different materials so direct comparisons are not always accurate or even possible. If you are comparing the same material and both test ILD/IFD on a 4" layer at 25% compression then they would compare and you would only need to convert lbs to kg but as you can see on the PFA site here

… comfort specs are measured differently in Europe so to even make rough comparisons you would need to know the method of testing for the firmness/softness of a material. A foam that was tested for IFD/ILD @40% compression would have a much higher number than a foam that was tested for IFD/ILD @25% (it would take more force to compress the same material to a greater percentage ofits thickness). There are also other methods used for testing firmness such as pascals or newtons that may be used as well. It’s usually best to use your own personal experience on a mattress as the best evaluation for softness/firmness and then use this as a reference point for comparing with mattresses that you can’t test in person that use the same type of firmness measurement scale.

Phoenix

It’s not “cork” but rather “coir”—a fiber extracted from coconut husks that is used to make rubberized bed rugs. Search for “coir” or “coir bed rug” and ye shall find.

Hi parra,

I think Bedimpediment is right because I don’t recall any post about cork and you are probably referring to the bed rug here.

Phoenix