Layering a bathroom floor. Concrete, aquapanels and heating

[tosborne88]

I currently have a concrete foundation to my flat's bathroom with plastic sheeting on top, insulated chipboard then lino. The lino is naff, chipboard and insulation is rotten and the thin plastic sheet is full of holes so seems to serve no real purpose.

I've bought some flexible adhesive, aqua panel, underfloor heating and some appropriate tiles.

Am I right in doing the following or would you do it differently?

Rip up everything back to the concrete. Secure concrete panels to floor with the flexible adhesive whilst silicon'ing round the joints, paint on some thermal reflecting primer, lay down heating then put adhesive and tiles straight onto primed board and wiring.

Am I missing any essentials or would you recommend something different?

I was thinking of insulation between the concrete and aquapanel but would this really provide a huge benefit or would the aqua panel with primer suffice.

Never done a floor from the ground (base layer) up before so appreciate the help.

Cheers!

 

[ree]

Have you taken into account how much any of your proposals will raise the FFL?
Or that, to do it properly, the bathroom will have to be completely stripped to leave only a bare concrete floor

Best practice with a concrete floor that appears to lack a membrane is to crack out the slab, and then build up to a desired level for a finished floor covering.

There are other alternatives, including sealing the slab, for what its worth.
Your difficulty is that you dont appear to have enough room to play with for U/F heating.

 

[tosborne88]

Yer the FFL will not be too much of an issue actually. although there was previously thin lino the chipboard and insulation was pretty chunky compared to the new aquapanel and there was previously a bit of a step down. Probably could get away with 5mm at most of extra material without creating a step up.

Cracking out slab isn't an option unfortunately as there are flats below but thanks for the advice.

Would you or anyone suggest getting some 5mm insulation? or would it not make that much of a difference after priming aquapanel

Thanks

 

[ree]

I wouln't use any insulation, you have the apartment(s) below providing some heat.

You could, at a pinch, go straight on to the slab, using a 1/2" notch spread and back buttering.

Use the same method on your Aquapanel if you go that way.

Stick the Aquapanel down with the adhesive - full coverage.

I dont see the point of priming the Aquapanel?

Under floor elec. heating is expensive to run. Towel radiators are cheap and convenient if a C/H run is nearby.

 

[tosborne88]

Awesome, thanks for the help ree. Will stick to the aquapanel w/ full adhesive coverage otherwise there will be quite a drop into it.

Yer no central heating unfortunately so all electrics. Got some cheap times of the day tariff so hopefully all the concrete will hold the cheaper heat in. Its certainly cheaper than the wattage that was in before, had a stupid size dodgy storage heater and a wall hung downflow heater. Will look so much better too.

Thanks again