A kitchen tile backsplash will protect your walls from steam, water and other moisture that can soil and damage them. If the wall above the counters and sink in your kitchen are smooth and solid, you don't need a backboard before you apply tiles to create a backsplash. This, of course, pertains to an existing kitchen application. If you are remodeling or building, you will want to use a backboard for your tiles. A backboard adds an extra degree of waterproofing for the tiled area and is extremely durable. Many builders prefer to add backboard to all walls before tiling, so it is generally up to the preference of the person doing the tile work.