Has anyone made a modular tile floor? I want to make a black & white tile floor for my morgue by using stick on tiles on 1/2 inch plywood. The problem I see is stopping the plywood sheets from separating. I'm thinking about screwing 1/2 inch by 1 inch strips on the bottom of the sheets. This will raise them up and I could theoretically screw one edge of a sheet to another but it seems labor intensive. Any ideas?