Hi,
depending on how much to pack out and what the mosaics are (stone, ceramic or ...glass).
There are packing mats available..... basically spacer pegs (square) joined end on on a sheet at about 2>3mm thick..I have used these and they do work..you cut to size.....
If walls are bad and you are on thick tiles and thin mosaics a thin tile >6mm insert can work too. but glass will/could show this through and the addy.
I also express to customers to get similar thickness tiles to borders..probs arise around switches when customer is adament about border height (Kitchen), window recess with vertical trims, shower screen fittings etc....
I have lost count of a "good tiler will get round this" remarks.....A good tiler informs the customer about this and why....and before they buy where possible. I have had no problems with tile shops I use exchanging borders for this reason..they havent lost a sale and are found to be extra helpful...so they dont mind.
The customers just dont think that far into a job...why should they, they are not tilers...thats why we need to help them.
