Why is this pipe facing downwards?

[GrumpyGrampa]

Hi, I'm not a plumber but looking for some advice. I have an old house, which has been added to and refurbished many times over many years by many different contractors. The other day, when trying to find something in an area I never go into I noticed a "musty" smell. I traced it to a "cast iron" pipe that was coming from outside at an angle downwards and terminated in a lead pipe (1.5 inches) that had been stuffed with paper and hammered together (poorly). There was a dampness at the end of the lead pipe. I traced the pipe outside to a cast iron stack that has nothing else connected to it. I assume it was used at some point in the past. I attach an image which I hope will explain what I've found. I filled the end of the badly hammered down lead pipe with expanding foam and siliconed it to death. Can anyone explain what this pipe may have been in the past?

 

[Chalked]

Hi
its a vent pipe. Old lee drainage was done like this. It’s not needed these days.
your plumber either should have reconnected it into the internal soil pipe, or cut it out right back to the soil pipe.
it will fill with water and leak without doing one of the above.

 

[GrumpyGrampa]

Hi
its a vent pipe. Old lee drainage was done like this. It’s not needed these days.
your plumber either should have reconnected it into the internal soil pipe, or cut it out right back to the soil pipe.
it will fill with water and leak without doing one of the above.

Thanks for the prompt reply. I'll arrange for it to be cut off at the stack outside. In the meantime, I presume blocking the lead pipe with foam and silicone will do no harm?

 

[centralheatking]

Thanks for the prompt reply. I'll arrange for it to be cut off at the stack outside. In the meantime, I presume blocking the lead pipe with foam and silicone will do no harm?

Hi Grumpy, I like your post, before you go ahead can you put up a sketch plan in elevation of this set up. I think I understand it but I would like more detail before I advise you and you go ahead
centralheatking

 

[GrumpyGrampa]

Hi Grumpy, I like your post, before you go ahead can you put up a sketch plan in elevation of this set up. I think I understand it but I would like more detail before I advise you and you go ahead
centralheatking

Thanks for taking the time to reply. I've attached a schematic - hope that helps

 

[centralheatking]

Ok I have it now, I would detach the naughty pipe as close to the soil stack as possible, even just cut it
then just bung it up with anything thats fits ...cork, rubber .bungs will do others on PF will also have their suggestions ...this is how we all co..operate ...centralheatking

 

[GrumpyGrampa]

Ok I have it now, I would detach the naughty pipe as close to the soil stack as possible, even just cut it
then just bung it up with anything thats fits ...cork, rubber .bungs will do others on PF will also have their suggestions ...this is how we all co..operate ...centralheatking

Thanks, I'll organise that.