Hi all, ive got a problem with an uneven wall in our new house, we have had a kitchen fitted with granite splashback and upstands across benches, but the wall isnt flat all walls in the house are the same), I can get a full finger down the back of an upstanding at places down to flush at the other end. I want to tile it myself, could I spray expanding foam to fill the gaps then tile from there do you think?