So my pool reno finally started. Company came to install coping/tiling yesterday and after laying the coping found there is going to be a 2-2.5" gap between the coping and deck. In measuring this morning, I found the bondbeam is 11". The coping they ordered is standard 12" and they are trying to do a 2" over-hang on the tile line on the inside of the pool, thus the huge gap. This is clearly a case of the builder ordering the wrong coping size. A little math tells me I really need a custom sized coping of 13-14".
They are proposing I either back the coping with mastic or a tile as shown in the picture. I think the tile looks ok, but it is going to make the expansion joint quite small. Thoughts?