Quarry Tiles & Electric Underfloor Heating

[kingscott]

We've discovered and exposed old quarry tiles in our kitchen. There's a couple of different sizes but I'd guess they're mid Victorian, or earlier. We'll have to lift and re-lay many of them due to subsidence, damage etc and would like to take the opportunity to put down electric underfloor heating; to keep the chill off the floor in winter, not to heat the room. Some concerns are:

Could the heating damage the quarry tiles?
Would the heating work with thick tiles?
Would the soft bed required for the tiles (sand on earth I guess) be OK with the wires?
Would it need a waterproof grout between the tiles?

Any advice would be appreciated.

 

[biffvernon]

Could the heating damage the quarry tiles?

No

Would the heating work with thick tiles?

Yes, but slowly. Make sure there is serious insulation lower down.

Would the soft bed required for the tiles (sand on earth I guess) be OK with the wires?

I guess so. But wires? Is this electric - the most inefficient form of space heating. Not so good for the planet.

Would it need a waterproof grout between the tiles?

I doubt it.

 

[geoff]

If you want to use the undertile electric heating mats, they have to be laid on insulating board.

I don't know of any underfloor heating which you could lay in sand - electric definitely not, even the wet underfloor heating has to be embedded in (insulated) concrete or clipped to polystyrene insulation and screeded.

The quarry tiles themselves should be able to cope with any type of underfloor heating - the thickness should not be any problem.

Have a look at this site - http://www.warmup.co.uk/ - they have loose wire and mat systems and instructions on how to install them.

 

[biffvernon]

Limecrete and light expanded clay aggregate (LECA) would be a good substitute for concrete.