Lifting old tiles to re-tile, help!

[Don]

I plan to re-tile our kitchen and was hoping for some advice on a bit of a mammoth job.

Firstly I need to remove the existing tiles (20cmx20cm 1 inch slate). I cannot tile over as there are external doors opening into the kitchen so that is not option. I plan to take them up with a jackhammer with a broad bit, going at them with the hammer almost horizontal to minimise damage to the sub floor.

My first question is that there is underfloor heating in the screed, is there any chance of damaging this when lifting the tiles? I am assuming the pipes are at least 2 inches below the surface. Can the concussion of the hammer cause damage?

Assuming I can get all the tiles up I expect that the floor will be somewhat uneven, how do I best pre this now for re-tiling? I assume a combination of taking out peaks and filling in troughs with levelling compound? Do I need to remove all the old thin set? If the floor is very uneaven can you get a sander to flatten it out? Will a 13mm trowel help to minimise any irrugularities?

Once everything is level is there anything else I should be doing before tiling?

The new tiles are cream marfil with flexible adhesive.

Any advice would be much appreciated!

[CTD inverness]

i think you have it nailed already, although i wouldn't count on the pipes being a full 2" below the surface.
remove as much of the existing adhesive as possible, bond the floor then use a self levelling compound to even up the surface. if you can get it level you could probably get away with a smaller trowel but dont go smaller than 10mm to ensure you get 100% coverage under the tile.
perhaps try a large bolster before the jack hammer just incase, you can get one called "the mutt" which is about 8" wide and on a broom handle i have used it once before and it lifted tiles off a concrete floor without problem.
hope this helps

[CJ]

I'd go very easy lifting the old slate..........you may get away with an SDS with flat bit.....you will need to cover everything as lifting slate is a pig of a job as it splinters everywhere. Thick blankets over all units. The more you can get up the better......slate/adhesive

Don't forget the safety specs as well

Then you will need to self level. Latex self levelling is wot I would use

Wet cut the marble.

& flexi adhesive (white) and grout.

Just in time for Christmas said the Mrs

[Dave]

You can use Mapei fire plan leveller for this job.......and is available from most branches of CTD....

[TilingLogistics]

Take the bulk of the tiles up as you have suggested and grind the floor flat

Kev

[Don]

Thanks guys, great advice, I'm not looking forward to this!