Smell under sink

ViktorOnopko

We've got a smell coming from under the sink. It appears to be coming from the waste pipe which goes out through the floor. It seems at its worst when there's been rain overnight.

Call a plumber or call the water company to look at the drains?

Aylesbury_Duck

Where's the manhole cover it drains to? Lift that and you might find the chamber full of dirty water, meaning there's a blockage somewhere in the drain beyond it. A £20 set of drain rods is a good investment and will clear most blockages.

ViktorOnopko

I think the extension is over the manhole cover. There's another one the other side of the house with a fence above it

Aylesbury_Duck

...and this is why it is not a good idea to build over manholes.

If the drain is blocked, you will have to hope it is blocked downstream of the built over manhole. Then you need to find the next manhole along and work backwards with the drain rods to clear the blockage. If water is still draining from the sink, I reckon the blockage is between the two manholes. The second manhole may be in your neighbours garden. I hope they have not built over that one as well...