I’m going to buy a pocketed innerspring (marshall spring) mattress with a visco-elastic memory foam outer coating, and the manufacturer allows choosing between 1.20 inches or 2.40 inches memory foam thickness. The thicker version will have an additional cost, of course. My question is about the possible drawbacks of the thicker version. Will I sink in the mattress? Will that make it hotter during summer time?
Hi dguerreiro,
I’d say yes, the thicker memory foam layer would allow more sinking in. It would depend what foam(s) or other materials are under the memory foam. MF is designed to sink in and mold or shape around the sleeper’s body, cradling. It can make sleeping temps a bit warmer in summer (all year round, but more noticeably in summer). How much depends on how sensitive you are to heat issues. The warmer temps in summer will probably allow the memory foam to sink a bit deeper/faster as MF softens with warmer temps than cooler ones. That could translate into a bit warmer of a sleep experience. The thicker version may be more prone to eventual body impressions over time, but 2.4" is about common or even on the thinner side of a lot of memory foam models. Most of the one’s I’ve seen offer anywhere from 3-5", some have even more. So even the ‘thicker’ option at 2.4" would be less prone to those issues I would think.
Not sure how you would test it out, but if you could find similar beds with those thickness of MF built in…see which feels better to you. Otherwise about the only other option might be to go with the thinner layer built into the mattress and if it’s not enough adding a thin MF topper. You can always add toppers, but you can’t reduce what’s built into the mattress if you feel it’s too thick. Hope that helps you out somewhat.
Hi dguerriero,
Only you can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved to be able to answer this based on specs (either yours or a mattress) or “theory at a distance” and the only way to answer either of these questions would be based on your own personal testing or sleeping experience (see mattress firmness/comfort levels in post #2 here).
When you can’t test a mattress in person or are uncertain about whether a particular design will work well for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) then the options you have after a purchase to make any fine tuning adjustments to your mattress that may be necessary at a reasonable cost may become a more important part of your personal value equation.
There is also more about the many variables that can affect sleeping temperature in post #2 here that may also help you to choose materials (including your mattress protector and sheets) that will have a better chance of keeping your sleeping temperature inside a range that would be comfortable for you but thicker/softer layers of memory foam would generally have a tendency to increase sleeping temperature vs thinner/firmer layers because they will form a deeper cradle around your body which would be more insulating and allow less airflow but the tradeoff of course is that thinner/firmer layers may be less pressure relieving or less suitable for you to sleep on.
If you tend to be closer to the oven side of the “oven to iceberg range” then I would keep in mind that memory foam in general tends to sleep warmer than other types of more breathable foam or other comfort materials.
Phoenix
I’m using an old inner spring mattress with about 30 years, so anything will be more comfortable than this one 
Of course, less pressure allows keeping the same position for a prolonged period of time, therefore having a more stable sleep.
As I am mostly a freefaller sleeper, and I’m afraid that too much memory foam would sink.
Hi dguerriero,
Too much memory foam (or any softer comfort layers) can certainly allow the heavier parts of your body to sink down too far and put you out of alignment over the course of the night which can lead to lower back discomfort or pain but the opposite is also true that comfort layers that are too thin or firm can also create pressure issues and in some cases cause alignment issues as well. The key is always to find the “right” combination of layers and components that is the best “match” for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences).
There is more about the relationship between primary support, secondary support, and pressure relief in post #4 here and there is more about “a perfect mattress” relative to each person in post #4 here.
Phoenix
I ordered the mattress with a 1.2" memory foam topping on each side, and I must say that I’m having an hard time to sleep on it. It seems that it applies too much pressure on me, maybe because I’m not too heavy, and I can not stand on the same position for very long time. I keep changing positions over the night, and I can not find a position that I can handle for too long. Needless to say, that my sleep has not been good, and the pressure got me lower back pain.
I can not return the mattress. Can I had a memory foam topping in order to mitigate this pressure issue?
Hi dguerreiro,
Yes … if your mattress is too firm for you then a topper can certainly add additional pressure relief and comfort so the combination would be a more suitable match for you.
Post #2 here and the topper guidelines and sources it links to has more information about choosing a topper that can help you use your sleeping experience as a reference point to choose a topper that would have the best possible chance of success.
Phoenix
I don’t think it is too firm, maybe it is too firm for my weight (my weight is about 130 pound). If I apply pressure with my body, I can feel the memory foam adapting to my body, but as soon as I lay still, I can feel the mattress pressing against my body.
Hi dguerreiro,
You would be the best judge of whether your mattress is soft enough for you but based on your description it sounds like it could be too firm and when you are experiencing excess pressure or pressure points on your mattress then it’s usually an indication that you could use some additional thickness/softness and pressure relief.
Phoenix