Floating floor (in)decision

[Workerbee]

Hello! My floating floor research continues...I'd posted previously about options for wetroom and kitchen flooring and got some useful feedback. I've now got three options.

It's an all-electric bungalow; bathroom is about 3.5sqm and kitchen about 20sqm.

 

Old floor: concrete slab, then 50mm polystyrene, and 22mm t&g chipboard on top. I'm keeping the concrete slab.

I'll add electric heating mats as a secondary heat to take the chill off the stone tiles.

 

Option 1: 50mm PIR then 22mm chipboard. Basically, what was already there. Not sure about chipboard in a wetroom - would I have to cover it with 6mm tile backer board, which will add to the height?

 

Option 2: Phenolic foam and gypdeck 18 gypsum fibre board. The best insulation (equivalent to 70mm PIR) but very expensive

 

Option 3: 50mm PIR then a low profile wet system like this instead of boards: https://www.elementshop.co.uk/profix-plus-panel-low-profile-system-20mm-depth-14-17mm-pipe?gad_source=1&gad_campaignid=17190333812&gbraid=0AAAAAoLtzP8iYrR1bZmw5I1Nv6dekc2Bc&gclid=Cj0KCQiAoZDJBhC0ARIsAERP-F_Hahv5xh4NmuS9ME_vn1_shoXRaCY0TsHN_pwsQQTPzPKcmpZu_QkaAnxFEALw_wcB Together with electric ufh, this would futureproof me if I ever got a heat pump. Would this also give me some thermal mass if I heated the electric ufh on overnight offpeak?

 

Are there any better options?

Thanks!

 

Edited December 2 by Workerbee
forgot to add third picture