Need advice on DIY hybrid mattress

Hi TMU,

Our couple is planning to DIY a Hybrid mattress with Coil support and Latex toppers and we need some advice. We are thinking about buying a King-size coil support layer and separate Twin XL Latex toppers to customize for each of us.

I am 5’4’‘, 140lbs and my wife is 5’2’’ 120lbs. I have lower back pain and we both sleep on our backs and sides (I think the frequent change in sleeping position is due to the heat building up on our current Casper mattress). I prefer a soft comfort layer on top of not-too-soft support layers and my wife hasn’t decided on her mind but usually prefers a firmer mattress. Here are my questions.

  1. Which coil should I get between Combi-zone coil, Quantum edge elite Bolsa and Caliber Edge? How firm would they be in comparison? Would the Combi-zone have more back support for my back? Would the zone splitting match my height?
  2. I am planning to add a 2’’ medium (28-32 ILD) Dunloop transitional layer and a 2’’ soft (around 22 ILD) comfort layer of Talalay. Would the total 4’’ Latex be too much for my weight and sink in too much? Should it be better to get a single 3’’ soft or medium layer or do a 2’’ transitional + 1’’ comfort layer?
  3. My wife usually prefers firmer options but she is not sure what firmness she would like for Latex. So she is thinking about tying a 2-inch medium Latex layer first for a few weeks and adding an additional firm or soft layer afterward depending on how she feels. Any comment on this?
  4. Would any frame with a normal slate be enough for this setup?

Thank you so much!