I live in a terraced house (built around 1900) and since moving in a few months ago have noticed that a drain smell comes from the lean-to drain each time water drains into it from the bathroom shower, sink, bath and kitchen sink (the toilet drains outside and there is a manhole cover outside the lean-to (about 2 meters from the inside drain that is smelling). The drain in the lean-to drains from the side at the bottom and there always seems to be some water at the bottom although it doesn't back-up. I'm unsure what is causing this and whether it would be worth buying a set of rods (however I have no experience) or whether it is best to get an expert out to diagnose the problem. I'm also unsure what a standard charge would be for this. Any suggestions would be much appreciated. Thanks
It sounds like the drain in the lean to is a gully. A gully is trapped which basically means the water that you can see in it is because the gully is a u bend like you would have under your sink or in your toilet. This is to prevent smells from the drainage system. It sounds like the drain isn't blocked ( which is why the water level doesn't overflow) but the drain may require cleaning. A decent company would visit you free of charge to provide a quotation to carry out these works. If you are based in Essex, Herts or London I would be happy to do this.
Kinds Regards Iain, Premier Drainage Company Ltd