Tiling on cold concrete (raft) floor

[Dad]

I am planning to tile a kitchen floor which is a thick concrete raft covered with linoleum tiles at present. I dont think the floor has a damp proof membrane.

The floor is very cold at present and I plan to install electric undertile heating mat before tiling. I think some sort of insulation will be required, but I don't want to install a thick layer that will significantly raise the floor level, as it will seem wrong to have a step up into the kitchen from adjoining rooms. Any ideas?

Also, will I need to remove the linoleum tiles first, which are stuck down with contact adhesive (Evo stik)?

[wetdec]

Hi Dad

Take the tiles up m8 do it right from the beginning. If you then email me your measurements I will sort you out a deal for underfloor heating and insulation and you can go from there

tiler

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[Dave]

What makes you think the floor has no Damp proof membrane.?..

[wetdec]

There probably is I would think as they generally insulate and dpm after they pour the steel work. If its not visible around the room then doesnt necessarily mean its not there, just hiding

Any worry on that score can be overcome I'm sure


tiler

..

[Dad]

House is 1969 build and when I took up the old laminate flooring, it was damp & smelly underneath. Also seems to be slight damp problem in one wall where the render touches the floor. Presence of these lino tiles (through the whole of the house & which seem to be original) made me suspect that they were the sole damp proof barrier - may well be wrong though!

Think you are right, I will have to take up the lino tiles in the kitchen. Just hoping I could get away with being a lazy bugger.

Any preferences on insulation anyone? Would 6mm Wedi board be sufficient? trying to keep costs down.

[Dave]

6mm or 10mm wedi would be fine.......usually when laminate is laid onto concrete fllor you have to lay it onto a dpc , so this could be why it has sweated etc.......it should be fine if you leave it to dry first.......after taking up the vinyls...

[Dad]

Cheers Dave

[wetdec]

How big is it Dad ??

tiler

[Dad]

This job went quiet due to client wallet - it's now live again!

Any preferences anyone on Insulating board? There seem to be plenty of options (Varme / Wedi and many others) I can only get away with 6mm, due to floor heights - which is best for thermal efficiency / price? What do you stick it down to concrete with? I will be removing the lino tiles as advised.... Also - which is best value heating mat? Job is approx 5sqM kitchen - will 150w/sqM be ok?