Hi Folks, i have a job to do for a builder who wants me to fix 600x300mm porcelain onto existing ceramic floor tiles that were fixed with Bal-Flex onto plywood, i have told him to remove exising floor but he says the floor is solid, the tiles are well fixed ( been down 10 years) and will be too hard to uplift. i have tried to talk him round to doing it the right way but he is adamant

What steps would you recommend ?

Would a decoupling mat be nessecary?

What about adhesive Keraquick & Latex plus ?

Your thoughts would be much appreciated

Welcome to TF.When you say solid,have you checked yourself.?Those porc tiles will be adding a lot of weight.

hi hammer,as you say i wouldnt touch it personally

Bal Flex was an excellent 2 part flexible adhesive and if there are no signs of cracking in the floor, I'd tile on top of those tiles no problem.
If there are signs of cracking go with a decoupling mat.
Remember only you can make the final call and any advice given is in good faith.
P.S. Don't forget to give the original tiles a good clean prior to using the appropriate flexible adhesive.

Originally Posted by timeless john

Bal Flex was an excellent 2 part flexible adhesive and if there are no signs of cracking in the floor, I'd tile on top of those tiles no problem.
If there are signs of cracking go with a decoupling mat.
Remember only you can make the final call and any advice given is in good faith.
P.S. Don't forget to give the original tiles a good clean prior to using the appropriate flexible adhesive.

Thanks John, no signs of cracking so what would you stick then down with ?

For the impervious substrate I'd use a polymer modified adhesive and allow longer than normal before grouting, especially for larger tiles.
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