Hi Mikes425,
Heat is a big issue for many people, and I see you and Phoenix had a past conversation regarding this. It looks like your mattress is 12.5" thick, which is not going to be a problem for sheets, even if you add a 2" topper. As Phoenix pointed out, your bedroom needs to be kept as cool as possible while you sleep. environments are sometimes the easiest fix depending on where you live.
Then, I am hoping you were able to look at the cooling sheets that Danican and other companies are offering. This too can be an easy fix.
Latex is temperature neutral and an excellent choice as a topper. you can get Latex in a variety of firmness, so I would suggest you engage in a conversation with some of the latex experts on The Mattress Undergroundfor their input. This can also help you from sinking into your pillow top, so it could be a win - win. I would suggest that if you get a topper, you place it above the mattress protector; they are notorious for warming up a sleeping surface based on their ability to stop moisture from entering the mattress.
I am also a big fan of wool as a temperature regulator. My company, Parklane Mattressesfeatures a variety of wool toppers that work well for this issue. Again, I would place this above the mattress protector so it can really “do it’s job”
Please be conscious of how much softer or firmer any topper will make your mattress. This is your chance to potentially change the feel of the comfort layers in your bed, while maintaining the support from your spring system.
I don’t know if I have added any insight into your current sleeping situation, but I hope I have given you a few things to consider as you move towards a solution.
Debbie Lewis
Parklane Mattresses