I just had my bathroom floor tiled and I am concerned about lippage. Before bringing this up with the contractor, I want to get an idea of how bad it is really. The tiles are 2.25" octagons with diamonds filling in the gaps on the ~12"x12" sheets. There are a few places in the bathroom where 1-3 of the octagons seem too high. Before complaining, I would like to measure the lippage on the tile.
I was thinking of using a penny, like I would to test tire tread (if I can't see all of Lincoln's head the lippage is too much), but I was hoping that there was a tool that might be more accurate and not have me with my cheek pressed against the floor for an hour or so. What is the best way to measure tile lippage?