Thin screed bonding advice

[daveo78]

I have a 3.5mx2m area to screed. Approx 45mm in depth. Cant be bothered digging out, insulating etc as most of the area will be covered in kitchen units.

There is no DPM: I've dug through it to put new water main in and the slab is about 6" thick with chicken wire as the reinforcer, nothing there to arrest rising damp

I've read this:

http://www.screeding.org/html/body_traditional_screed.html

For simplicity I want to go the fully-bonded route with a DPM (i.e. using 2 layers of epoxy).

Can anyone recommend a particular epoxy product to use for this? There seems to be a massive variation in price between epoxy coatings. Marine epoxy is >£80 for 2kg packs. Sikadur 31 slow set is £20/kg pack and Sikadur 32 is £30/kg from my local Travis Perkins. I need approx 2-2.5kg for this job and another one.

Any advice appreciated.

 

[simonjay]

I don't know much about epoxy, but you may be able to use a sand cement screed with a reasonable amount of SBR in the mix to make it waterproof. Use a cement / SBR slurry to bond. Usually ratios are provided on the SBR container. Got to be easier than bonding down a DPM with epoxy.

 

[Deluks]

Liquid dpm, (see the stickies in the flooring section) then fix some 20mm marmox board with tile adhesive and tile over that. Better than a cold slab by far. Could even put a small heatmat in there if you fancy splashing out a bit more, don't need to run it under the cabs so wouldn't cost much.