Hi,
Ive been working with a local outlet to get just the right mattress feel. They will build for me the following:
two 1" latex 19 ILD on top of
one 1" polyurethane foal that is 1.5 lbs on top of
a Lauraflex coil innerspring (14 gauge)
This outlet seems to have a good reputation (and is listed on your site here as reputable). The owner seems to enjoy getting his customers the right fit. My concerns remain in the polyurethan 1" layer. He swears that this layer will not be a problem, and he gives a 12 year guarantee. He says that he readily works with customers after the mattress is sold to make further adjustments to get the right fit.
Do I insist that this polyurethane layer get changed to the Poly HR 30ILD or a latex 30 ILD?
Vince
Hi vince,
I would agree that 1" of 1.5 lb polyfoam would not be an issue.
If they are one of the better factory direct manufacturers that I think highly of I would also consider their advice to be accurate and in your best interests as well 
Phoenix
Thanks Phoenix
This is a seriously excellent website! I will be sure to recommend it to everyone.
Now, time to make a donation to express my thanks!
Vince
PS: Im glad I asked the question because I got the impression than one should never use an poly foam under 1.8lbs, but in my case it seems quite acceptable.
Hi vince,
The 1.8 lb guideline is usually what I use as a minimum guideline for a polyfoam support layer but lower density polyfoam in thin layers (usually around an inch or so) in either the quilting or comfort layers or in some cases thicker layers under more durable layers or in lower budget mattresses or in a two sided mattress are perfectly acceptable inside an appropriate budget range.
Phoenix
Your answer begs the question: if budget really isn’t an issue, how strongly would you recommend changing out the 1’ ploy layer (that is 1.5 lbs) to either a latex or a poly HR/HD layer?
Hi vince,
That would change the feel of the mattress so for me it would depend on what it was replaced with and how it felt to you compared to the one you have tested. It would be a preference issue in other words.
From a purist point of view, I would replace it with latex but this will change the feel of the mattress and you may not like it as much. It’s not uncommon for manufacturers to use an inch or so of polyfoam (in the quilting or top layers) to customize the surface feel of the mattress and reduce the natural resiliency of latex for those who prefer this or are used to a less resilient feel. With layers this thin … foam softening will have much less of an effect on the overall mattress than if the polyfoam layers were thicker (there is less to soften although of course it still will).
So replacing it with latex would slightly reduce the effect of foam softening but since this effect would already be small because the polyfoam layer is so thin … it would make it more a matter of preference than necessity … although my tendency would lean towards changing it out if that was possible at a reasonable cost.
Phoenix