A problem I had with ZONING my mattress
Feb 23, 2008 10:08 PM
Location: L.A. area
Joined: Jan 18, 2008
Points: 1161
As most of you know I have been experimenting with my mattress which basically consists of, top to bottom, top 1/3 zone to middle 1/3 zone:

TOP 1/3 of mattress (shoulder area)
1" soft PU foam
1" medium HR foam
2" soft visco foam
springs

MIDDLE 1/3 of mattress (hip area)
1" soft PU foam
1" medium HR foam
1" very firm HR foam
1/2" super firm HR foam
springs

This is my current configuration which seems to work pretty well so far, though I'm still experimenting.

But at first the zones I had made were killing my back and I figured out why:

On the next to top layer, under the soft pu layer, I had different densities of foam so there was a line right at my waist which was the division between, say, a medium one
inch layer and a firm one inch layer. So that "line" where the medium piece met the firm piece was actually creating a pressure point or line of pressure all the way across
my waist, or above my waist (25" down from the top of the mattress).

What I realized is that I HAVE to have the same density of foam on that top layer (next to top layer, not counting the topper, it's the top layer). Otherwise I was getting a line of pressure across my waist from the difference in densities. I assume I also need to have the topper be an even firmness all the way down the length of the mattress.)

So once I began using Medium firmness or medium ILD for that next-to-top layer for both my top 1/3 and the middle 1/3 of my mattress, that pressure line disappeared and
now I am doing much better! I still have a much softer top 1/3 for my neck area, however, by making the layers UNDER the top layers be much softer for my shoulders.

This may not be true for everyone, but it was certainly true for me!

Hope this might help someone who is zoning. I'm curious if anyone else has ever run into this problem.

Re: A problem I had with ZONING my mattress
Reply #22 Mar 7, 2008 5:24 AM
Joined: Sep 7, 2007
Points: 476
jimsocal wrote:
I too would like to try a 1" to 1-and-1/2" visco foam topper, maybe a 3lb one. At first I thought I wanted to try the 5lb but then I slept on my 2" 4lb one and realized it was too hard for me. A 1" 4lb might work but I think if I buy one I'll buy a 3lb one. I do have a 3/4" 3lb one but it isn't quite thick enough and it's really more like 1/2" because it's convoluted.

I love the feeling of memory foam but what I found is that often it feels good the first few nights and then softens up too much. Maybe if it's just a thiin topper for softness, though, that is not an issue. It was surely an issue with the 3" stuff I was trying and even the 2" one: Not enough support, too much sinking in.


Jim, you might like the 1" visco from Overstock.com. I've had it on my bed since July and it still feels the same way it did when I bought it. Maybe because it isn't very thick, but just enough to give the bed a little bit of soft cushiness. It runs a bit on the skimpy side so get it bigger and cut it down if you can. I love the feeling of memory foam too, but 3" would be too much of a good thing for me. With just one inch lack of support isn't an issue because you don't sink in enough for it to become one.
This message was modified Mar 7, 2008 by cloud9