providing the substrates are solid..it wont be a problem,
However if you did not do the original install you dont know how the tiles were fixed (buttered,dot and dabbed,serrated etc.) if you are going to guarentee this type of project i would want to have done all the prep......otherwise you are cutting corners.....cutting corners can (and does) cost mucho dinero...
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p.s could be done is not the same as shold be done!!!!!!!!!!!!!!!!
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Lets face it....customers sometimes try to pressure you to be cheaper in your install........but at the end of the day if it goes wrong who do you think is going to be blamed....i dont think the customer is going to
remember saying to you go over the top of the tiles....all they will "know" is its leaking into my new bedroom.........
Tanking onto existing tiles? 
Linear Mode
