Most of the time, we suggest that silicone caulking be used to replace old caulking on commercial buildings. Silicone caulking lasts three times longer than urethane, and it costs only 30% more to put in. We prefer to use silicone caulking instead of urethane, but if you need urethane caulking, we can get it for you and usually give you a price for both. In the last few years, Concrete Polishing Solutions has come out with a new silicone caulking that is less likely to pick up dirt and less likely to leach chemicals than their already low dirt pick up and low chemical leaching properties.