I see, I wasn’t aware of that sorry about the confusion on that! Well this seems to be a high traffic thread so hopefully someone with more information on that topic will see your question and respond.
Hi I’m new to the forum and want to ask a question re latex layering, I’m in NZ and have less access to companies with knowledge of layering latex and ive only ever seen and tried single 6-8 inch layers to my knowledge Which firm is too firm and medium feels good but lacks deep support. I’ve found a local maker who can do it and has suggested 6inches of firm with 2 inches on top of medium of both natural latex However they are not sure of which type and what the ratings are (they’ve promised to ask the supplier) the mattress will be split and finished with natural wool and mostly cotton
(with little polyester)cover.
My wife prefers firm and is a lighter weight back sleeper and I’m a 5ft 11 165lb side sleeper, therefore she has option of firm side if medium side too soft and I’d sleep on medium side.
My question is if you think this option may still be too firm for a side sleeper and if you’d recommend another inch of soft latex added or completely reconfigure things on my side to the common 3inch firm 3medium 3 soft that I’ve seen mentioned lots on the forum… I guess I’m trying to achieve a medium feel with deep firm support that previous medium latex one piece ones haven’t for me but without pain from too much firmness for a side sleeper. Sorry I cannot be more specific at this point regarding density measurements but assume the ratings should be fairly similar to your US companies.
Many thanks
ND
Hey gyrosmith,
Welcome to Mattress Underground Forum 
! Thanks too for your question.
I liked TD-Max’s comment, 'Why not get the mattress right the first time. It got me to thinking about how I would apply basic engineering principles to getting it right first time. If I’ve understood the excellent papers here on TMU the first thing to get right is spinal alignment.
Thanks for your kind words on the site, good to know you’re finding the resources here useful. Looks like you have read Phoenix’s guidance, “Five steps to your perfect mattress- Overview”, specifically Step 3/ testing a mattress for “support” or its ability to keep your spine aligned in all sleeping positions.
Does anyone know of any peer reviewed scientific studies of how various mattress constructions affect the spinal alignment of a range of body weights and shapes? I cannot find anything on the Internet.
That’s a tricky one, gyrosmith. You would hope there was more online scientific data regarding spinal alignment paired with these variables, given the number of sleep disorders people suffer from, the number of sleep research centers out there and the amount of interest in better sleep quality overall. However, there isn’t. You can see quickly it’s a complex subject from a science standpoint as there is no way to make claims that one type of mattress construction is superior to another based on any number of metrics. Those claims have not been supported uniformly in a measured way because of the multitude of variables involved (sleeping environment, sleep preferences, etc.) In other words, there are many factors affecting sleep in addition to spinal alignment and pressure relief, Phoenix discusses others here in “Your sleeping style, preferences, and statistics- Overview”.
I’m moving your question to the general forum and renaming it “Mattress Construction and Spinal Alignment: researching body weight/ shape studies”, perhaps our TMU trusted members and consumer subscribers will weigh in. If you do find what you are looking for, please update the forum, would be interested in what your research says.
Thanks,
Sensei
If your wife prefers a firm mattress, then 2" of medium over 6" of firm would certainly accomplish the goal of having a firm mattress. I wouldn’t be able to say if that setup will align with her specific preferences, only she would know that, and I just wouldn’t be able to make a guess to that end. My best advice would be to get the mattress as 2" of medium and two 3" layers of firm so that you could replace one of the 3" firm layers with a 3" medium if she finds the mattress to be too firm, or she could add a 2" soft topper to the mattress if needed for some extra contour and pressure relief. Conversely, if she finds the mattress to be too soft at medium/firm/firm she can try firm/medium/firm, or firm/firm/medium even. Based on your information and the fact that you didn’t mention that you prefer an especially firm mattress, I would normally recommend soft over medium over firm for you side, if that’s an option. I’m not sure if the company you plan to buy this from has the option for 3" layers instead of a 6" core, or if they allow for exchanges, but this is just my best initial advice. Please also note that, as you stated, without knowing the ILD’s of the layers, what that company calls “medium” may be different than what we call “medium.”
Hi Sleep Ez, thanks for your reply and yes that makes sense what you’re suggesting. I’ve now found out that the latex is Dunlop and soft is 20-25, medium 30-35 & firm is 40-45 ILDs according to distributor, and only comes in 3 thickness sizes 150mm 6", 50mm 2" and 30mm 1.25"approx.
My wife is happy with her side choices but as I’m a side sleeper (and sleeping on a unlayered 200mm latex single medium density slab has given me both lower back discomfort and hip pain periodically) so I think I like/want something between medium and firm with both deep support and pressure relief, I am taking your advice of firm, medium then soft on top but trying to work out the best proportions with the thickness available.
Do you think 100mm firm with 50mm medium then 50mm soft on top would be a good choice? Or should I play around with some 30mm 1.25 " slabs to have a little less soft on top and end up with a slightly thinner or thicker mattress although it’s easier to make the total latex as 200mm just under 8" so I don’t need to adjust my wife’s side.
Many thanks
ND
Given the limited options, I think 50 mm of medium then 50 mm of soft is the best option. I wouldn’t be able to say in advance whether you’ll find that to be suitable, I just think that’s the best choice at this point.
hi there, i also live in naples florida and was wondering if i can connect with you regarding your mattress choice i am having trouble finding vendors in SWFL
Hello Peacockave
Thank you for reaching out. If you have questions and would like to discuss by phone, please feel free to call us at 480-966-8731. We are happy to answer any questions. Thank you!
SleepEZ