I am just doing ceramic 12x12 tiles and sanded grout with 1/8th inch lines. I bought a latex exterior paint and just used a small brush and just painted the grout. It wicked up almost instantly and wasn't excess wipe off. That was yesterday. I only did half of the bathroom floor because it is slow tedious work! Hope to finish the rest later today. I ordered some water based 20 yr grout sealer and will seal over the grout lines with that. I figure if there are areas that need touching up from time to time, a weekend will do it every few years and the paint is cheap, so I think I will be pleased with it.
Gordon your floor looks really shiny, how did you manage to use a sanded grout and not scratch it? We laid a shiny porcelain tile in the shower and used unsanded grout there with 1/8th inch lines. I love the really shiny tile in a shower.
