We have a 1975 home. We noticed a water stain on our ceiling in our kitchen. It is about the size of a silver dollar. The master bedroom shower is directly above. We stopped using the shower in that bathroom until we solve this problem. We understand that the ceramic tile floors and walls back in the 70's were set into mortar. We have been told that we may have to replace the membrane which is either under or over our mortar base on the floor because it has probably rotted out by now. Are there any products out there that will solve this problem without a tear out of the upstairs bath shower floor? We could regrout and then recaulk the perimeter of the shower floor (we do see an itty bitty crack in the grout between the floor and wall and we suspect this is where the water is coming from. We have heard of a product called spectra that is waterproof expoxy grout. Would this work? Or could/should we just have the floor tiles lifted and maybe one row around the perimeter too, put a new membrane down and then retile with maybe a stone/pebble type floor and just keep the original wall tiles. We want to solve the problem but don't want to tear apart the bathroom. We have been told that if we remove the tiles from the mortar we are sure to have cracks occur around the house from the pounding out of the tile. We just did a downstairs remodel/addition and don't want to ruin that and have new cracks in our walls and ceilings. Another person said that you could just retile over the existing tile and that the mortar base is the best base you can have. However, retiling over the tile would make the shower smaller and if continued to match the whole room, floor and other tile walls, it would cause the floor to be higher too. Help! We just want to fix the leak, not do a major remodel. Are there any products that could help?