Wet Underfloor Heating on existing concrete slab

[mgould]

I am going to build a house extension and part of the kitchen will have the existing concrete slab floor and the other part will be in the new extension. I want to have wet underfloor heating across the whole room.

I am comfortable with building the new extension floor allowing for the required insulation and then laying the underfloor heating in the screed.

However the existing floor slab does not have any insulation. Hence if I add insulation and the screed on top I will be raising the kitchen floor which is far from ideal.

Can I grind off the required depth from the existing slab or do I need to break it up and lay a new slab at the required depth to allow for the underfloor heating?

Any ideas?

Thanks!

[tonyjackson]

underfloor heating needs the insulation. Have you concidered a floating floor system! the underfloor heating pipes are set into insulation on top of the slab. I don't know what type of floor finish your having if its a wooden floor then there is no great problem and the insulation could be the same thickness as the old screed.