Natural stone on wooden floor with electric UFH

[newmodel]

Hi Guys, I'm 6 months in being a tiler, I've done lots all my life and sold the dam things for 10 years so I'm after a little advice on a upcoming job please.

10 Sqm of natural stone (they have not chose which stone yet) on a upstair wooden floor and they want electric under floor heating too. The flor is chipboard and pretty solid in most places, theres a couple of bits that moves etc a couple of small holes from old pipe work and a place where a chunk has splintered off.

I was thinking firstly, 6mm hardibacker, stuck and screwed and then the cable laid on top of that.....

1. Should I level over the wire, as I have tiled directly over it before but that was on an insulation board and only 2 Sqm so it was easy going?
2. Should I use a decoupling membrane like Durabase as well as the Hardibacker?
3. Is all Stone ok for this situation, my instincts tell me to avoid travertine like the plague and probably marble too?
4. Any other advice please?

Thanks in advance guys

 

[hmtiling]

firstly deflection(bounce) needs to be addressed. If that means lifting floor and reinforcing so be it. If floor is solid then insulation(marmox etc) ,ufh, latex, decoupler then tile

 

[Unused Account 1]

I just did a job with ditra matting ,with the ufh wires fit in the matting ,you can self level over just to cover the wires

 

[newmodel]

I've seen that matting, looks good, I know a lot of tiler who always go on about using Ditra.

 

[newmodel]

Hi guys, the customer has just changed their minds and do not want stone now, they are going for porcelain tiles instead, will I still need the crack mat underneath or will hardibacker or insulation boards be enough, the floor is pretty solid to be honest and when I said there are a couple of bits that move I meant there are a couipld of loose boards that just need screwind down but theres not a lot of bounce at all?