Liquid DPM, underfloor heating and Self Levelling 18mm

[PhilStebbo]

Hello all – some advice welcome.

I have an existing kitchen floor – concrete slab, no DPM or insulation. I need to bring it up to a new level which is 18mm higher than its current level. Within that 18mm I would like to:

Install a Liquid DPM (as per instruction on forum)
Lay a foil to reflect heat
Fit an electric heating element
Finish for limestone tile

Given the DPM instruction I’m thinking that the most appropriate method would be to:

1. Clean/dry concrete slab
   
2. Prime with watered down p131
   
3. Self level with acrylic to depth of 8mm
   
4. Apply 2 costs of DPM
   
5. Prime again
   
6. Lay foil
   
7. Lay heating element
   
8. Self Level, burying heating element to required level using a latex levelling compound
   

First - does this sound right?
If so - I’d welcome people’s thoughts and advice on which products that would be most suitable for both levelling compounds and heating element.

thanks
Phil

 

[dazlight]

Hi Phil, bit out of date that info.
So you could
2- prime with water
3 - Ardex NA at 8mm
4 - one coat of Ardex dpm 1c
5 - prime neat with P51
So on

 

[PhilStebbo]

I think I have found a better approach:


Use KA Tanking Slurry on the existing concrete substrate
Key with an SBR bonding agent
When SBR bonding agent is tacky – use a rapid flex adhesive and lay 10mm warm-up boards
Over warm-up boards lay electric heating element
Then screed with latex to cover

I was told that the DPM might not be needed as the adhesive and warm-up boards are water proof


Thoughts anyone?

 

[mikeey84]

Just one note, I have used KA tanking slurry before with great success, a lot easier than messing around with epoxy resins etc.

Also- without a full load of insulation, ie 60-100mm, alot of your heat is going to be wasted in the slab