Connect toilet to existing stack in block of flats?

[rosieplumb]

We live in a modern-ish block of flats. We want to remodel our flat (no structural changes), which the Lease allows but we need a Licence to Alter. We want to site an en suite bathroom where our kitchen currently is and have a smaller kitchen. The existing soil stack is cast iron and appears to be 100-110mm diameter (from restricted view). Our architect and experienced builder (with own plumber) think there is no problem. Extraction to existing outlet is no problem. However the Management Committee is hostile to our renovation although they did not give any reason for refusing us. They did not mention the issue of the toilet specifically but I am trying to cover all possibilities. Is there any consideration about connecting to the soil stack, which currently takes six storey's waste from washing machines and kitchen sinks with In-sinkerators. We would be willing to tank the new bathroom if requested. Also I would not be replacing our Insinkerator as I do not think they are eco-friendly and the washing machine would be relocated to other area. Thanks.

 

[Whyme]

six storeys....erm the commitie would probably be more agreeable with architect drawings because your moving a bathroom in a flat and the shared waste is cast. all depends on what it will look like from outside and will the run and connection look out of place etc etc. ( you can connect to cast with plastic but im sure your plumber will know that, why would you have to tank the bathroom, is it a wet room or in a celler).

 

[lame plumber]

cos when the plumber cracks the cast soil the neighbours dont want to get wet ceilings if cast is internal 🙂, re neighbours, no one likes changes in flats just in case theres cock ups and floods and if the management committee says no not a lot can be done as majority rules in these situations.

 

[tamz]

Night shift plumbers? at premium rates obviously :smile:

 

[snowhead]

Who does the stack belong to?
Who is responsible for maintenance of it throughout it's whole length, not just blockages but deterioration?

I'm sure I can see a crack in the cast stack at roughly the level the O.P needs to cut into it???

 

[rosieplumb]

Wow! Thank you all so much for prompt replies. I really appreciate it.

Yes, there were detailed architect's drawings, and architect and FMB / NHBC builder ready to meet to discuss. The SVP is internal and boxed in.

The owners own share in Freehold with elected Management Committee making decisions. Owners pay for deterioration through service charge, but if you think about it, by adding a bathroom we aren't using the bathrooms MORE, rather we are spreading the load, so to speak.

The (12 year old) new build plumbing wasn't wonderful and by correcting in our own flat we are reducing damp through concrete - we have silverfish - disgusting (anyone have a solution to that?). And there have been leaks in the past.

Actually, majority doesn't rule. According to the Lease, they cannot unreasonably withhold consent to alterations, and we can take them to Court or tribunal if they do. But nobody wants to do that. I know they are being unreasonable because they don't want the hassle. They wouldn't meet, they wouldn't discuss. We don't HAVE to tank. It was just an idea to appease them in case of any leaks.

I am just trying to make sure that we are correct and careful and haven't missed anything. The issue I wondered about is introducing black water from the w.c. into a stack that now has just grey water. But the grey water isn't recycled, and would never be: it includes sink, Insinkerator, and dishwasher waste, as well as washing machine waste.

Obviously the water would have to be cut off and drained for the plumber to connect, so that no one is flooded. That's happened in the building before.

 

[lame plumber]

you all own the stack but as you are finding out the management committee is the ones to give approval and they cant with hold permission without good reason. but you go upset them and they probably have a legal insurance policy for the building that will pay for them to take you to court, can you afford to go to court? the inconvenience of cutting off other flats to do the work may be an issue for them. Its a situation you wont win if you go at it like a proverbial bull, you need to get on the committee yourself to win this one, softly softly is the only way youll win with out going to court which is stupid money down the drain

 

[stevetheplumber]

it will depend how the existing waste stack joins to the drains wether you can add a wc to it there may well be a gulley at the bottom in which case you cant run a wc into it

 

[lame plumber]

it will depend how the existing waste stack joins to the drains wether you can add a wc to it there may well be a gulley at the bottom in which case you cant run a wc into it

good point, seen it done with obvious results later down the line

 

[iiplumbing]

Hi Rosie

There are also considerations to the height and distance that interconnecting branches can be placed.

BTW how is your plumber proposing to cut the CI stack? And what proposals is he giving to make sure no-one above your flat uses their appliances basins etc whilst he is cutting and when he has made the cut what is he proposing to use to connect the new branch in with? I.E. a new 4" branch is going in, how is he going to connect it to the existing stack above and below?

I'm sure your plumber has the answers.

From a contractural point of view, if they have refused your application then you are within your rights to ask for the specific reasons that they refuse. If they cannot or do not give you a reasonable explanation then will have to take the next step (legally) because without their say so you are dead in the water, because if you go ahead then your work can be stopped in its tracks by legal order if necessary

I think its a bit like the party wall agreeement that exists for owners of joined property, you have to inform them and enter into an agreement, if you dont and they get nasty about it then they can take out an injunction to stop the work until such times as an agreement is in place!

There is more to this than I think is apparent, because if you have a legit Architect and builder on board then they would be doing all the legwork for you, unless they are not instructed to do that bit

Hope this makes sense and helps

Russ

 

[PowerFlusher2]

you all own the stack but as you are finding out the management committee is the ones to give approval and they cant with hold permission without good reason. but you go upset them and they probably have a legal insurance policy for the building that will pay for them to take you to court, can you afford to go to court? the inconvenience of cutting off other flats to do the work may be an issue for them. Its a situation you wont win if you go at it like a proverbial bull, you need to get on the committee yourself to win this one, softly softly is the only way youll win with out going to court which is stupid money down the drain

But only if he can get permission to cut into it!!!!!!!

 

[rosieplumb]

Hi Rosie

There are also considerations to the height and distance that interconnecting branches can be placed.

BTW how is your plumber proposing to cut the CI stack? And what proposals is he giving to make sure no-one above your flat uses their appliances basins etc whilst he is cutting and when he has made the cut what is he proposing to use to connect the new branch in with? I.E. a new 4" branch is going in, how is he going to connect it to the existing stack above and below?

I'm sure your plumber has the answers.

From a contractural point of view, if they have refused your application then you are within your rights to ask for the specific reasons that they refuse. If they cannot or do not give you a reasonable explanation then will have to take the next step (legally) because without their say so you are dead in the water, because if you go ahead then your work can be stopped in its tracks by legal order if necessary

I think its a bit like the party wall agreeement that exists for owners of joined property, you have to inform them and enter into an agreement, if you dont and they get nasty about it then they can take out an injunction to stop the work until such times as an agreement is in place!

There is more to this than I think is apparent, because if you have a legit Architect and builder on board then they would be doing all the legwork for you, unless they are not instructed to do that bit

Hope this makes sense and helps

Russ

Thanks Russ. It does make sense. There was nothing the builder and (RIBA - legit) architect could do if the Committee wouldn't meet, and by now the Architect is taken up with other projects. It became a legal matter. That is not a step we want to take, so I am still trying to get a handle on it. By the way, there was a Structural Engineer's drawing as well, showing we were not disturbing existing structure.

What are the height and distance considerations you referred to?

You mentioned a new 4" branch (for the w.c.). We've only had an oblique view of the existing stack, it looks 100mm or maybe 110mm, not 4". By the way, reaching in, it also feels a bit rusty. Is that normal?

It is a bit like a Party Wall Agreement. In that case as I understand it, if the other Party does not reply, a Party Wall surveyor is appointed to act on their behalf. In this case if the other Party refuses without valid reason or doesn't reply, we apply for a determination, but that is a legal process. We can recover costs. There is a case to say that we can go ahead with the works if they refuse unreasonably. Of course they could issue a writ, but our defence would be that we are entitled because they refused unreasonably.

But that is not a road we want to go down. We tried to do everything properly, we didn't start by going like the proverbial bull as mentioned by someone in the thread, I think they responded like proverbial bulllies. We were prepared to listen to their concerns and co-operate. Now I just want to make sure that there are no obvious genuine issues with our plans. Hence my post. As I wrote, I don't want to discuss our situation or the law, I just would like a better understanding of the building issues, the plumbing one the most perplexing to me, hence this thread.

I take it that draining into a gulley mentioned in the thread is not an issue with a modern multi-storey block of flats with basement. Again, thanks.

 

[iiplumbing]

Hi Rosie

OK I understand what you require now

First, as long as the stack you are intending to use is a foul drain, then technically, provided you comply with the connections regulations (which mostly concerns connections that are comming in from both sides which I dont think is an issue here) there is nothing you are proposing that is not allowable in the legal sense.

Basically, its a soil (foul) stack, you wish to connect to it, you can, job done.

From a practical point of view, there are a whole load of reasons why its not easy but thats not your question.

Hope this helps

Russ

 

[stevetheplumber]

if the stack is cast iron its either 3 and a half inch, 4 inch or six inch

 

[rosieplumb]

Hi Rosie

From a practical point of view, there are a whole load of reasons why its not easy but thats not your question.

Hope this helps

Russ

Thanks, Russ. I should very much like to know the reasons it isn't easy. And what determines whether it is a "foul drain"? Must it be if it takes waste from the sink, dishwasher, etc, and is a certain diameter?

 

[tamz]

It is easy enough with a chain cutter and a timesaver

 

[iiplumbing]

Thanks, Russ. I should very much like to know the reasons it isn't easy. And what determines whether it is a "foul drain"? Must it be if it takes waste from the sink, dishwasher, etc, and is a certain diameter?

Trust me it wont be easy, things like this are never easy

You are correct, it would seem to be a foul drain but, I'm not on site and I have not surveyed it and I cant say for sure so I need to add a note of caution to my post

regarding your thoughts on drain size, if its cast it will have industry standard internal/external diameters, us plumbers refer to it as 4" knowing that for cast its 110mm OD (ish) and plastic its 100mm OD (ish) whats for sure is that its not 3" or 75mm or some kind of rain water pipe size (65mm ish)

Measurements pipe diameters and thier imperial/metric equivalents are a whole different avenue of discussion.....

Russ

 

[lame plumber]

just a note, the party wall act applies to neighbouring properties with no connection or ownership connection ie 2 neighbours with a semi linked together. Remember your dealing with leases and property ownership issues which a bit more complex and a real pain to resolve most of the time.