Leak in Tricky Position - Will this work?

[john51]

We had a new bathroom built last year. Mould on the kitchen ceiling shows that it has been leaking for a while and the builder called in the plumber to investigate.

He took out a panel from the floor and found that the leak is on the connection of the shower waste to the 4" pipe. The waste pipes are close to various beams and it would be difficult and disruptive to re-do the pipework. He therefore decided to slap a lot of solvent weld round the various bits of the strap boss and told me that he couldn't guarantee it would work but it would weld the plastic together. He asked me to test after the weekend.

I am not convinced that putting solvent on the surface of a connection will weld anything, as you presumably need pressure between the two parts that have been coated. I was also concerned that the expansion and contraction of the 50mm shower waste will stress the repair and re-open it at some time in future.

Do you think that this will provide a long-term fix or is it likely to break down again in the near future. I don't want the hassle of remembering to access the cupboard and check it periodically. What would you do?

Thanks,
John

 

[Roy_66]

We had a new bathroom built last year. Mould on the kitchen ceiling shows that it has been leaking for a while and the builder called in the plumber to investigate.

He took out a panel from the floor and found that the leak is on the connection of the shower waste to the 4" pipe. The waste pipes are close to various beams and it would be difficult and disruptive to re-do the pipework. He therefore decided to slap a lot of solvent weld round the various bits of the strap boss and told me that he couldn't guarantee it would work but it would weld the plastic together. He asked me to test after the weekend.

I am not convinced that putting solvent on the surface of a connection will weld anything, as you presumably need pressure between the two parts that have been coated. I was also concerned that the expansion and contraction of the 50mm shower waste will stress the repair and re-open it at some time in future.

Do you think that this will provide a long-term fix or is it likely to break down again in the near future. I don't want the hassle of remembering to access the cupboard and check it periodically. What would you do?

Thanks,
John

Hi John,

Can you add a photo to help people with their replies. Perhaps there are alternatives that could be fitted.

 

[john51]

Hi John,

Can you add a photo to help people with their replies. Perhaps there are alternatives that could be fitted.

Thanks, Roy. I've just tried to attach a couple of images but the upload is aborted with the message "This file was not an image as expected" I'm struggling to find some help on the site. Anyone know what it is doesn't like?

 

[Jock Spanners]

Hi John,

Without a photo it's hard to say. However if he removed the boss (assuming it is ABS and suitable), cleaned it, dried it and refitted it using plenty of glue on both survaces it should be fine. The problem with most bosses it that they usually have a nut and bolt to the rear. That's not an issue on an external soil pipe but might be internally where space is limited.

 

[rpm]

I have used solvent weld before in this sort of situation as it melts the plastic a little to form the weld, however I have only done so to buy time untill I can return to do the job properly.

 

[SimonG]

If it hasnt been removed and re glued I would doubt it will hold.

 

[john51]

I'm still not able to attach photos despite saving them at smaller size in case they were too big. If anyone recognises the error message and can advise, I'll try again.

Thanks for your replies so far. The strap has a ratchet type fitting that you squeeze together rather than a nut and bolt. I'm not sure whether that makes it easier or not.
I didn't realise that you could take the strap off successfully after it has been glued in place. If so, and the pipe can be cleaned up, then presumably a new boss can be fitted. I don't think the plumber I have had considered that but even though it's difficult to get at, that would be a much more promising way forward in my book.

I agree with the general consensus of views that a smear of solvent on the outside surfaces doesn't sound like an effective solution.
[automerge]1588425980[/automerge]
I've uploaded some photos to Flickr for those interested. The link below should hopefully work.

John McQuin has shared 5 photos with you!

www.flickr.com

 

[Scott_D]

The gap may have been big enough to force some solvent in and create a seal.
In reality it probably needs cutting off and doing again.

 

[Jim Goodenough]

A bit off topic but Terrain used to sell "gap filling cement" in a tube especially for attaching bosses to soil pipes - maybe it's still available ( they also used to sell 157.5 degree bends which were useful).

 

[john51]

Not off topic if it worked! Certainly sounds a better bet than something that is designed to weld a joint from scratch, but I guess that the problem would be in making sure you got in the right gaps in a position where it's hard to see what's what.
Thanks.