I have just tiled an external concrete slab with sandstone tiles. I've
applied grout and cleaned up with a sponge, but I didn't get the tiles
completely clean. Anyway there is excess grout on the surfaces of the
tiles which is hard to remove.
Anyone have any advice on how to get it off? Would high pressure water
blasting clean it off and is water blasting a DIY job or would I need a
contractor to do it?