Mysterious smell in ground floor living room All aspects of plumbing questions and answers, help, tips and information

[zagva]

Hello,

We've got a mysterious smell in the ground floor of our terraced house. It has been coming and going sporadically over the last 2 years or so and at the moment (during lockdown) every few days. We've checked our water and heating pipes which are all normal.

The smell isn't like sewage but more like detergent/dampness. It's worse in the living room and you can also smell it at the air brick in the front garden. It also smells in the back garden a little bit but not really at the air brick and not under the kitchen extension - i've made a few holes under the kickspace to check for dampness and found none. The smell in the back garden seems to be more in the air as if it's coming from one of the neighbours. It's worse when the sun is out, especially in the first part of the day when it's on the East facing back garden/kitchen side.

2 and a half years ago we had some building work done on the garden shed during which the kitchen waste pipe got moved so that it was emptying into the garden instead of the drain for a few months. When we found the problem we noticed the waste pipe seemed to have moved very slightly as it no longer fit into its concrete casing. Since then I dug the soil out around it but haven't found any leaks there and the soil is as dry as the rest of the garden and also doesn't smell.

The neighbours on both sides also have kitchen extensions where their washing machines are but neither seems to think there is a problem with them. I've checked our washing machine and there's no leak. I've also tried a peppermint oil test in the drain pipe that seemed to be negative.

I've made a few small holes and put a cheap endoscope camera down in the kitchen and living room but from what I can see it's always dry underneath - I've also opened a floor board under the stairs and it's the same. The smell is never particularly strong at any of the holes. Our floor is very difficult to take up so I'm trying to avoid that.

Has anyone dealt with problems like this before? Have any useful ideas or advice on how to proceed?

Many thanks,
Zac

[stoneyboy]

Hi zagva
If your washing machine discharges into a standpipe I suggest you check this is clear and check the pipe.
Regards S

[zagva]

Hi S,

Thanks for the post. The washing machine and standpipe are both in good order - no leaking. There's almost no smell in the kitchen, it's in the living and a little bit in the back garden - even though the kitchen is between the two.

Best,
Zac