I sleep in one exact spot on my bed at all times. I am not a petite person but I’m not enormous either. I have a fairly expensive firm coil spring mattress I’ve had awhile. Since it only has mattress on one side, there is only 2 ways I can flip it to get out of the dip. I want to buy a new mattress and want to know what kind resists the “dip” the longest. Memory Foam? Gel foam? Latex? I have spinal injury, so it’s important I find the right mattress. Because of my back issues, I frequently use a heating pad if that matters. Thanks in advance for your feedback.
You are wise to look at the materials in a mattress instead of a brand name.
Latex is the most durable and longest lasting of all the foams. It softens more slowly and gradually than other foams and it will also last significantly longer before it breaks down (and forms dips). I would choose between blended Talalay or 100% natural Dunlop as these tend to be the most durable although almost all latex is more durable than most other foams.
Memory foam can also be long lasting but not as long as latex. While there are many factors involved in the durability of memory foam … the single most important is the density. Look for memory foam 5 lbs density or more. Bear in mind that all memory foam will soften significantly over the first few weeks and then the softening will become more gradual.
Most of what people call “gel foam” is memory foam with some gel infused in it. Because gel is heavier than memory foam … if you infuse gel in 4 lb memory foam (medium quality), it will become heavier and can weigh as much as 5 lb memory foam. The “base foam” is still 4 lb however and will tend to have the durability issues of 4 lb memory foam. The lowest quality of memory foam (3 lb and even less) for some may only last a matter of months.
There are also gels that are only gel (not infused in memory foam) such as Technogel or a “buckling column” version such as Orthogel or Intelligel which are made under license of EdiZone. These are very durable however they are also very expensive and the cost may not relate to the benefits for many people.
Polyfoam has a very wide range of quality and can range from very cheap and low density (in some cases under 1.0 lb) which will break down very quickly to very high quality (HR polyfoam of 2.5 lb density or more) and more expensive. Medium quality polyfoam will usually start at about 1.8 lb density and would be suitable for a mattress support core or for use with certain types of construction in the comfort layers of lower priced mattresses. The higher quality the polyfoam the longer it will last although in most grades you will see more rapid early softening as well and then the softening rate will become more gradual. You will rarely see HR polyfoam in the comfort layers of most commercial mattresses as it is more expensive than the cheaper polyfoams.
So in a nutshell, of all the foams … latex is by far the most durable. It will not soften as much or as quickly as others (softening can happen even without any “dips”) and it will also not break down as quickly (when the dips start to appear). The best rule is to avoid all polyfoam (or at least more than an inch) in the upper layers of a mattress unless you are buying it from a local mattress manufacturer who will tell you the quality they are using and how long you can reasonably expect it to last. Memory foam can be a good choice for some but is not a good idea to use with any heating devices as this will make it far too soft and I would tend to avoid it with back issues as well as it is not a supportive foam (which is why it is never used in the support layers of a mattress).
If I was in your shoes … I would be looking for a latex comfort layer (thickness and softness to be deterrmined by your weight distribution, sleeping positions, and sensitivity to pressure) over a support core of either an innerspring, HD polyfoam (1.8 lb density and preferably higher), or latex (either Talalay or Dunlop).
Thanks. Would a latex topper compensate for the dips in my current innerspring mattress? :unsure:
What abt this with the 4" med firm topper? http://www.absolutecomfortonsale.com/latexfoam.htm
Once your mattress has dips or has become too soft … then a topper is not the best way to go. If the materials are worn out … then the topper will just follow the soft spot or the dip and even though it may feel a little better … it may create new problems. Toppers will help with a mattress that is too firm on top … not so much with materials that are either too soft or worn out.
Absolutecomfortonsale sells good quality material but I would certainly hesitate to put 4" of anything on top of an existing mattress. This in addition to the soft (degraded) material that is already on top of your mattress would turn the previous comfort layers into support layers and would likely create another issue (support layers that were far too soft). It would be rare than someone would need more than a couple inches of latex even on top of an existing mattress that was too firm.
I would also question the IFD (also called ILD) ratings of their Dunlop latex. To my knowledge, there is no pincore Dunlop that has an IFD as soft as 16 - 18 in that density even though many sites list their Dunlop as being very soft. I believe that this is a misunderstanding that comes from a very different method of expressing IFD in Asia which has not been translated into North American terms correctly. Their Dunlop is certainly high quality and is now from Thailand (it used to come from Sri Lanka) but I doubt it is that low ILD.