can you tile on to old floor tiles?
i have an old floor & a new floor next to each other, i dont really want to disturb the old floor as it seems 'ok', would it be advisable to tile on top of them or remove them & start over?
i will be using ceramic on top of ceramic tiles

Yes it's completely possible, but you do find that after some time there is more likelihood of tiles loosening. Check that all the current tiles are soundly bonded to the walls - you should be able to tell just by tapping them and the sound they make if they are loose.

Also degrease all the current tiles to strip off anything that could affect them bonding, sugarsoap is useful. When retiling, make sure you use a good adhesive that is suitable for retiling over tiles. Finally, make sure that your joints do not match up with the old ones - a bit like the way you would lay bricks.

Hope that helps!

Strip the tiles for your peace of mind , its a couple of hours chasing up and possibly some self levelling compound, if not you may have height issues with thresholds & appliances, which causes extra work.

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Natural stone specialists mosaic, porcelain and ceramics