I have a 3600 Sq. Ft. flat roof, it has an old tar and gravel that is not in that bad of shape. I would like to know about different sealants that can be sprayed or mopped on existing roof. The two that I’ve looked into are Wet Jet from Pace and Unisil from GAF. If anyone has used either of these or any of the other many brands that are available please let me know what you thought of the results.