Advanced search

Drains problems - where to start?

(17 Posts)
RandomMess Sat 19-Mar-16 16:42:00

Moved into 60's house and did a basement conversion.

So kitchen and shower room in basement and waste water is pumped up to the drains.

Ground floor kitchen removed, ground floor bathroom still in use.

Soil pipe is all internal and doesn't seem to have a flue (?) thing anywhere coming out of the stack?

So when the kitchen sink/shower room is used the house smells - mainly on the ground floor.

I think the increase in the cesspit pushes the air out somewhere.

Any solutions/where to start investigating?

engineersthumb Sat 19-Mar-16 20:45:32

I'm no expert on this one but I'd try and trace where the pump outlet is connected. If it's connected directly to the stack I'd first check its not leaking. If on the other hand it's emptying into a gully outside then it could be what's laying in the line/tank causing an issue and needing cleaning. I've never heard of an unvented soil stack but I'm not a plumber. If the ground floor bathroom is still in use and doesn't cause the problem I'd have thought everything up the line was ok. Have you tried leaving the tap running for half an hour and seeing if it subsides?

RandomMess Sat 19-Mar-16 21:45:12

The pump emptied direct into the outside drains/sewerage.

The smell does dissipate after a while on its own.

What I can't rule out is old kitchen pipes not blocked off properly (next to the ground floor bathroom) or does the smell actually back fill into the house for the sewers outside???

It's where to start sad?

engineersthumb Sat 19-Mar-16 22:07:19

Does it empty into an open gully? Has the smell been there from the beguiling?

RandomMess Sat 19-Mar-16 22:19:32

Straight into the drains underneath the outdoor manhole.

We never lived in the house before the basement work and the smell is on the ground floor but def caused by using the basement plumbing...

engineersthumb Sat 19-Mar-16 22:32:16

So the smell was there from when the building work was undertaken?

RandomMess Sun 27-Mar-16 19:17:02

I really don't know sad we didn't live in the house before the basement conversion was completed!

engineersthumb Sun 27-Mar-16 21:56:01

This is only my amatures take on this but three possibilities spring to mind. If it's not used regularly waste water could be laying in the line/pump. Not a lot I could suggest other than use regularly and possibly use bleach, though check pump instructions. Second, air is being forced up the line from the sewer cap when you pump out. This shouldn't happen as all waste traps should have a full water seal, check each trap to make sure that they are in place. Make sure that the dishwasher and washing machine waste connections either connect to the trap (so are above the water seal) or if tapped into the line directly also have a water seal (u bend etc). Lastly it occurs to me that if the upstairs and downstairs are connected to the same line the pump could be pumping over one of the ground floor traps. Run the shower in the basement then have a look/listen at all the waste traps (ground floor sinks/basins/showers). If it's gurgling or you can see water running then this is likley the issue. If its either if the last two issues then you need to alter the waste pipe arrangement. If it was recently put in then I'd contact the contractor and ask them to verify.
Hope that is of some help.

PigletJohn Mon 28-Mar-16 09:47:16

If it's a 1960's house it's unusual not to have the soil pipe venting to the atmosphere at roof level. Maybe that was cut and closed during alterations, and a Durgo or similar fitted. They are inclined to be troublesome.

Most likely there is a plumbing duct in the corner of the kitchen and the bathroom where the soil pipe is (or was when the house was built) and if you follow its route it would pass vertically through the loft and out through the roof. See if it has been cut off and hidden away and if there is a plastic cap on the top. There should be a "manhole cover" that you can look down for signs of blockage.

You use the word "cesspit." If you are in the UK you will not have one, but you might have a septic tank if you are not on mains drainage. Are you?

Look at the building plans for the conversion that were used for Building Regulations approval. Who did the design?

RandomMess Mon 28-Mar-16 18:10:07


OK so in the basement conversion there are 2 "wells" one collects the rainwater that is then pumped out into the freshwater drain. The other collect waste water that is then pumped up into the main sewer drain. This is what I was referring to as the cesspit???

The main sewer drain before the basement conversion was visible and I cannot see anyway or anywhere there was any sort of vent on it... From the horizontal pipe that ran through the basement it goes up to the toilet/ground floor bedroom but there is no vertical pipe up from that room anywhere... no soil pipe up in the loft anywhere!!!

However that does sound of sound like the issue, I assume I need to get some sort of vent on the sewerage drain This would then stop the air pressure building up internally which is what seems to cause the smell?

I am going to draw a sketch of the house (it's a weird set up) to try and explain what I mean to see if that can help me. At the moment I wonder if I need to get a soil pipe mounted externally for all but the basement stuff (sounds expensive) but that still leaves me with a queries over whether it would actually help sad

PigletJohn Mon 28-Mar-16 19:04:39


RandomMess Mon 28-Mar-16 19:40:01

Yes sump, that is what it is called grin

I have had a drive around the street to look at the rest of the houses built at the same time 1959-1960 they were finished. We have a purpose built chalet bungalow but more of them are true bungalows. It would seem that a fair few of them have the additional of external drain piping to add on the flue/vent thing... perhaps this has been an issue in other properties.

I have attached a sketch of the internal soil pipes - hope it makes sense.

PigletJohn Mon 28-Mar-16 20:59:26

pumping to a foul drain from a sump is not usual in UK homes, so I would hope that the design was prepared by the manufacturer or an experienced installer, and approved by the building inspector. Order copies of the BR plans from your local authority, or download them from the website, to see how it was supposed to be done, then try to verify that it was built as designed.

If the drains are being pressurised during pumping, there might be a leak of fluids or gas, which is undesirable.

Who drew the plans?

RandomMess Mon 28-Mar-16 21:22:30

Which plans?

The basement conversion was done by a specialist conversion company so the did the sump pump stuff. Met the building inspector when he came out and he had a very good look around.

My personal opinion is that there is gas leak being created in the original drainage system somewhere from the pressure of the sump being added to - when the liquid is added to, the gas increases but the level does rise enough for the pump to empty it.

So sometimes there is a feint temporary smell above the sump, the worst of the smell is definitely on the ground floor and sometimes is really bad but not every time that the basement sump is added to. I can get into the area where the pipes from the sump to the main drain is and it doesn't seem to smell there.

Assuming I can find every joint possible what is the best way to seal them? Or would have a vent from the soil pump help anyway as well?

PigletJohn Mon 28-Mar-16 21:27:33

To get building Regulations approval, plans have to be submitted to the local authority, so you should be able to get copies. These can also be useful when contemplating any future work.

RandomMess Mon 28-Mar-16 22:35:36

Okay will get hold of them and check all the paperwork. Unbelievable I managed to somehow delete most of the emails and attached paperwork I had regarding it all sad sad

It sounds like I need to go ahead with my plan of taking up all the ground level flooring to inspect everything and see if there are any joints or old pipework that hasn't been sealed off properly sad

user1491295098 Tue 04-Apr-17 09:42:59

Message deleted by MNHQ. Here's a link to our Talk Guidelines.

Join the discussion

Registering is free, easy, and means you can join in the discussion, watch threads, get discounts, win prizes and lots more.

Register now »

Already registered? Log in with: