Floating floors: compression vs vibration

[Workerbee]

Hello! I know floating floors have been discussed before, but I wanted to check my thinking with you guys before going ahead. 

I want to install natural stone and electric ufh on top of a floating floor in the kitchen and bathroom. Currently the buildup is concrete slab, then 50mm polystyrene, a vcl then 22mm t&g chipboard and carpet/stick-on vinyl tiles. Current ideas are: 

- 60mm ravatherm XPS, bonded to slab with approved adhesive, then 6mm insulated tile backer board. This would eliminate the floating floor as everything's bonded. XPS also has very high compressive strength; but does this also mean low vibration?

- 50mm PIR or phenolic, then 10mm insulated tile backer board. Again, I could bond this with pu adhesive; it's only being squashed, so the fact it's foil faced shouldn't matter?

- PIR/phenolic then insulated routed XPS boards for wet ufh pipework, then electric ufh mats above. I don't have gas, and heat pumps aren't currently suitable for my property, but this would give electric ufh now and the option for wet ufh should a suitable product come to market in the future. 

- if none of these is an improvement, then leave as is.

 

So it's basically xps Vs PIR/phenolic: very high compressive strength vs better insulation. But does compressive strength mean low vibration for fitting stone? Can PIR be adhesive bonded to the slab?

 

 

Thanks!

[Nickfromwales]

OK!!

 

Give us the depth you have to play with, from slab up to FFL please, as there's a lot of info but it's all a bit tricky to correlate.

 

And why electric UFH? It's the most expensive thing you can run, and is this for supplemental heating or full-on space heating?

[Gus Potter]

37 minutes ago, Nickfromwales said:

Give us the depth you have to play with, from slab up to FFL please, as there's a lot of info but it's all a bit tricky to correlate.

Agree with @Nickfromwales Is the floor separating two different dwellings? 

 

If you are adding load to the floor have you checked that is ok? 

 

A drawing would help a lot. You need to start with the basics and develop from there. You can maybe see it but for us it's difficult to comprehend as a complete floor design. If we can't understand it then little chance your builder will and the prices you get will reflect that.

[Workerbee]

Thank you for the replies, and sorry for my poor explanation! It's a bungalow, and in terms of compressive strength I think any of polystyrene, PIR or XPS should be fine. I've done a crude drawing of what's currently there:

 

 

The finish is currently carpet or tile. I'm basically just thinking of replacing the polystyrene with either PIR or XPS (ravatherm seems to have a decent lambda value), and replacing the chipboard with insulated tile backer board. This will mean I can bond everything together with suitable adhesive so that it's technically no longer floating, because the finish will be natural stone, which can obviously cause issues on a floating floor otherwise.

 

I wondered if the ravatherm might have two benefits over PIR: would the fact it's not foil faced mean it bonds better? And more importantly does the higher compressive strength equate to lower vibration, or is that a separate characteristic?

 

It's an all-electric house, so that's why I'm thinking of electric ufh. It'll probably be secondary heating, but given I'll be installing oil filled radiators it'll end up being just as expensive!

 

Thanks again.

Edited Sunday at 21:19 by Workerbee