Building a Mattress: Have a few questions

[phoenix]

Hi androiddd,

I have a Ph.D. in psychology but I think Phoenix, you should be awarded an honorary Ph.D. in Mattressology! What a thoughtful and deep reply.

Thank you for the kind words!

What is high resilience foam and where does one buy it?

High resilience polyfoam is technically polyfoam with a density of 2.5 lb or above, with a compression modulus of 2.4 or above. It’s discussed in more detail here in this article. Some better sources of which I am aware for polyfoam are listed in the component supplier post here.

I read your other article about progressive layers, and it sounds like since we are both side sleepers at least part of the time, we would need a comfort layer on top of 2 inches, and then an intermediate layer of 2 to 3 inches. Perhaps a 2 inch 5 pound memory foam on top, followed by a 3 inch layer of Dunlop latex in a medium firmness. The memory foam tends to have an ILD of 14 or so so I’m wondering if the Dunlop should be 20 or more like 29 ILD as the progressive layer?

A 2" + 2" or 2" + 3" combination certainly could work well. The 20 ILD Dunlop would be closer in plushness to the memory foam, but might be more of an abrupt transition to the polyfoam base (depending upon which you choose). The 29 ILD Dunlop might “bend into” either polyfoam core better, but it could be a bit more of an “abrupt” transition between that and the upper memory foam layer. It all depends upon your personal preference. Remember that all of the layers work together to provide overall comfort, but the uppermost layers will have the greatest impact upon comfort perception.

If I don’t want to spend the money on the Dunlop latex, which costs about $100 per inch and a queen size, what kind of poly foam would you recommend for that intermediate layer? Should be flat foam or convoluted foam? Should it be high resilience foam? Particularly on the guest bed that I’m rebuilding, I want to keep the price down.

If you want to keep the price down for the guest room mattress, for the transition you may want to consider 1.8-2.0 lb polyfoam. I personally would choose a solid sheet versus convoluted.

I see what you mean about not splitting the comfort layer between 5 pound and 4 pound memory foam as they probably both feel pretty similar. I do wonder if it would make sense to split the bottom support layer into ILD 29 and ILD 50 pieces, perhaps 3 inches thick for each? I would assume the 29 firmness should go on top. But they could be swapped later if necessary. I may be overthinking this

You certainly could do this, and yes normally the 50 ILD would be on the bottom with the 29 ILD on top. This would provide a more “gradual transition” to the deepest support layer. And if you do this, it would impact what you would choose for your upper transition layer. I always recommend a “bottom up” approach when analyzing these scenarios.

Not a question just a comment. I have used Foam by Mail before and other than slow shipping I haven’t had problems. As far as I can tell their prices for memory foam are much lower than anywhere else, but if there’s another vendor that has similar prices but better quality I would certainly be interested in knowing their name. For latex they seem to be more in the same ballpark as other vendors, with costs for Dunlop being about $100 per inch of thickness and the queen size. (Of course there are very high-priced latex vendors too, which almost double those prices.) Most of the complaints that I read on your site seem to be about confusion between Dunlop and Talalay latex, but FBM no longer even sells any Talalay latex.

If you read through all of the comments on the forum about them, you’ll see that there was more than what you mentioned. What I believe to be Dunlop represented as Talalay, evasiveness with specifications, uncertainty about sources, repetitiveness of support factor numbers (questionable specifications)…(from one of my previous posts) There is more but I think you catch my drift. I won’t support a business which I believe follows less than ethical (by my standards) business practices and they have a long way to go and a lost reputation to make up for before I would consider buying any of the latex foam they sell or suggesting anyone else does. There are many who “love” them … but I believe that is only because they don’t really know what they actually purchased. There are also many more who don’t … and with good reason. If you choose to deal with them that’s certainly your prerogative, but I’ve been pretty clear regarding my position for the reasons stated here and elsewhere on the forum.

And to repeat what I posted earlier, some better sources of which I am aware for latex and polyfoam are listed in the component supplier post here.

Anyway, I want to thank you from the bottom of my heart for such a smart response and this will greatly help me in planning this bed build. I’ll be ordering the components over the next few days, and building the bed in about two weeks. I’ll update on success or failure.

I’ll look forward to your updates. And there are no failures…just steps along the learning curve.

Phoenix