Hello from Perth Western Australia,
I have read a lot of information on this site (there is nothing quite like it in Australia) and I did post a very long discussion recently but it has no replies as yet. Since then I have more specific questions so I thought to start a new post (shorter).
I am considering a full latex mattress from a local shop which stocks Heveya certified organic latex mattresses (I think they are made in Belgium). The latex core they use is 15cm, 7 zones, in soft, medium or firm. The soft is 70 Kg/M3 and comes with a slightly softer (65Kg/m3) 5cm comfort layer. I have asked what their medium and firm density core layer are for comparison and hope for a reply soon.
I read somewhere on your site that the recommended ILD for the comfort layer is 19-24 which roughly equates to 65Kg/m3 so the Heveya comfort layer, would be within that range. However, 5cm for the comfort layer is a bit less than what I saw recommended on this site (I saw 3-4 inches over a firmer core for a side sleeper). But maybe thinner and softer is okay if it works for the sleeper.
The mattress comes in a quilted cover made of organic bamboo and cotton. It is advertised as being 4cm but I don’t know if this is a full 4cm on the top or 2cm top and 2cm bottom and have asked for clarification as if it is 4cm this would be outside of the 1inch guideline I have read on this website (I recall a post by Phoenix that said any quilting shouldn’t be more than an inch).
My question is whether there are rough guidelines for sleeper weight and latex density for the core layer? My husband is 85kg and sleeps mostly on his side but sometimes on his back. When we tried the Heveya he said he liked the soft density core layer (70 Kg/m3) with the slightly softer comfort layer (65Kg/m3) rather than firmer core with the soft comfort layer. The salesperson didn’t actually say whether the other option on display was firm or medium, just that it was firmer than the soft option. I am thinking my husband might be better with a medium core layer and the soft comfort layer.
I am 49kg and the soft/soft was good for me. We can get the mattress split so that it is medium/soft on one side and soft/soft on the other.
I am also wondering whether the fact that the core layer is a solid 15cm (around 6 inches) would make a difference and perhaps a 70Kg/m3 core with a soft 5cm comfort layer would be okay for an 85kg side sleeper?
Does a thicker core layer provide more firm support than two thinner layers? Is a thicker core layer the sign of a good latex mattress?
I look forward to some responses to this shorter, more specific post.
This depends on a few things. The size of the person, their specific support needs, the firmness of the layers. As a rule, a thicker, firmer layer is going to provide more firm support. However, a thick soft layer may do the opposite which is why you don’t want to decide on thickness alone.
That said, it’s not very common for companies to put a soft support layer in a mattress unless its specifically requested.
Thanks for your reply and links to more information. So, would you say that 70kg/m3 is “soft” for a support layer, and unusual? I am waiting for them to tell me what the medium support layer is in kg/m3. Heveya have soft, medium and firm options as standard and overall they say that their mattresses have a density of between 65-85kg/m3. If the “soft” is 70 then perhaps the medium is between 75-80 and the firm is 85??
The Heveya is Dunlop latex and they don’t talk in IDLs. With a 70 core layer and a 60-65 comfort layer it may be that the thicker layer ends up feeling as soft as the thinner layer? I feel very confused about density and firmness. My husband is just going by “comfort” but I think we need to consider some of the theory around density and BMI.
So, I read up on the links and trawled through old posts and articles around this topic. I calculated our BMI - I am 20.4 and my husband is 28.4. But I still don’t have any idea whether we should have different requirements for latex density and/or firmness and I don’t think I am getting the difference between density and firmness!
I am also unsure of how we can find a comfort layer to suit us both when it appears from what I have been reading that a lighter person may need a thinner but softer comfort layer and a heavier person may need the same softness but thicker. We don’t have a choice of a split comfort layer. It is either 60-65kg/m3 over 70kg/m3 for me and 60-65 over medium (whatever kg/m3 that is - the salesperson is yet to respond) for my husband.
I think we will go back and try the firmer support layer again. My husband is tired of looking and he just wants to settle for the version he liked after trying both options that were on display for about 15 minutes each. His rationale is that if it proves too soft before the 100 day free trial and exchange runs out he can change it to a firmer layer then. He says he would feel embarrassed by returning multiple times to lay on the same mattresses!
I would appreciate any further insights you or others may have. I know Phoenix has had long and detailed discussions with many others (do they still contribute to this site?
