How Deep Are The Pipes For Water-Based Under-Floor Heating Set Into The Screed?

[ladybirder]

I'm hoping The Builder can answer this for me. Problem is I want my bathroom floor tiles taking up and new put down but I am finding it difficult to get anyone to do the job once they know I have underfloor central heating. They say it could be more trouble than it's worth. I suppose they are afraid of fracturing a pipe when removing the old tiles. Is there really a danger of this happening?

[The Builder]

Right, questions first, Lady B.

Upstairs or downstairs?
If downstairs, solid floor or suspended timber?
Electric or wet U/floor heating?
Ceramic tiles?
Roughly how old is the house?

[The Builder]

Oh dear, just noticed you said screed......... so, downstairs, solid floor?

Wet system with pipework set into screed over insulation over concrete then?
The depth will depend on which system was used.

If pipework was laid directly over insulation, then a standard 50mm screed will give roughly a 30mm cover over it. No danger of any damage when the tiles are removed... unless gorillas are involved. Anormal person would have no trouble.

Another system involves threading pipework around an array of plastic "egg-boxes". The sticky-uppy bits of the egg-boxes keep the pipes separate. This can have a standard sand & cement screed laid over, but cover may be slightly reduced (depending on thickness of screed)... maybe 25mm cover.
Still shouldn't present any problem with tile removal.

Another possibility is a sloppy, pumped screed poured over egg-box layout (self levelling) This is thinner... maybe as little as 20mm cover.

Anyway, whichever you have, my only proviso would be to remove the tiles manually. i.e. without using electric breakers etc.

A breaker can be used as long as it has a wide flat chisel, and the machine is pushed as near horizontal as possible to avoid digging into the screed.

Any sensible tradesman should be willing to do the job. Bear in mind that if the worst happens, it's no big deal to repair the pipe and carry on, but I can't see any reason why it should happen.

[ladybirder]

Sorry TB, had to take the dog to the vet. Yes ground floor, , solid floor, wet, ceramic, new build 2008, wet. Got a tiler coming NOW and we'll see what he says and if he'll do it. Due 5.30pm.

I'll be back. Thank you for your reply. Just what the doctor ordered:-)

[ladybirder]

TB I've found this among the bumph when I bought my flat ""Floors: 10mm Sound Foam, 65mm Polystyrene insulation heating pipes 75mm screed".
Don't know if that helps at all but by what you have said if the job is done carefully then it shouldn't be a problem. Thank you for that. The chap due at 5.30 is a tiler not a builder like the others so fingers crossed.

[The Builder]

75mm screed Ladybirder? Excellent.

Even more cover on the pipework... possibly at least 50mm.

Even the most clumsy would have a job hitting the pipes. Tell him they are at least 2" under where he's working.

[ladybirder]

Tiler's been and he is very happy to do the job. He reckons it will take two days and he's removing a bath panel and putting a nicer one in for me as well. And has to lift up the toilet and basin. Should get a quote tonight or tomorrow.