Hi we have recently moved houses and the drains in bath and basin in the bathroom smell really bad, only after usage. we have tried all sorts of cleaners, had a plumber fit anti syphon traps, and the problem still exists. so far it has cost us nearly £ 400 and I am concerned the plumber is missing the real cause of the problem. We have had Dyno Rod check the drains for blockage - none found. The Bath is along the exterior wall, so the distance is no more than 2m and the basin has it\\\'s own waste pipe ( not connected into each other). This is the main bathroom and there are additional bathrooms in the house that are not experiencing the same problem. all help/suggestions appreciated.