Cost for converting Open Drain to Closed Drain ?

[m1ke]

Hi ,
I'm completing a loft conversion in a shared building, and have just discovered that the existing Soil stack to which I'm connecting a new toilet is terminating on an Open Sewer drain (see picture). The builder didn't check, and this will be the first foul water connection to the stack, so it needs to be converted to a closed drain. It's at the rear of the building connecting to a sewer at the front.
I'm therefore interested if anyone has some ball-park figures as to what it would cost to convert this open drain to a closed drain that would be suitable for foul water. Pipe on the right is the existing soil stack, on the left is the rainwater pipe.

Soil Stack

• m1ke
• 1 Aug 2013
• 1

Open Soil Stack

Cheers - M[/img]

 

[Hugh Jaleak]

Assuming the existing drain is connected to a foul sewer, then should be fairly straightforward. Remove existing gulley, expose drain from gulley. Fit rest bend for foot of stack, and a new gulley to accept rainwater pipe.

Biggest issue may be if the pipework goes under the building, getting to it to make a new connection. Pricewise, how long is a piece of string?

 

[m1ke]

Hi Hugh - thanks for the response.

> Assuming the existing drain is connected to a foul sewer,
It definitely is, so they should only have to replace the entry which does disappear under the building from where it's shown.

The reason I'm asking for a guesstimate is that there is some resistance to the change, and I suspect I may be stung with some random high amount as I will be the one paying for it.

From your description of the effort perhaps 3 days work for a couple of guys that know what they're doing, and a day to tidy it all up plus materials ? £1,500 ish or am I being cheap ?

 

[mfarrow]

I'd say they're more likely to bite your hand off.

What needs to be clear though, is that it is unusual to find a stack for foul waste being open like that, without someone reporting it in the past for being smelly. Be sure that, although it looks like a sewer, it isn't a storm drain which you'll be unpopular for if you contaminate it.

 

[m1ke]

I admit that it is an unusual set-up (old property, history of undocumented maintenance work), and ironically a change to a closed sewer is being resisted by the ground floor as they seem to not get that it really is an open sewer rather than a storm drain or some such. It must smell, but I can't test.

Anyhow your responses have given me some food for thought - Cheers !

 

[rjm2k]

If you removed those 2 black grilles from it then there's no way that can be for toilets is there? Surely it would be covered by poo and loo roll all the time? Unless there's a building wide macerator?

 

[mfarrow]

The only way to tell for definite would be to find the manhole on your property and check that whatever you flush down the loo (blue roll is useful) and pour down the drain (some kind of colouring) ends up at the same point.