I have a serious problem with a newly constructed house for which there appears to be no answers forthcoming from the builder etc. There is a drainage leak inside a major support concrete beam (supporting the overhang of the upstairs section of a house which is all concrete block construction). 1/Is there any way to seal off this leak internally as to try and access this solid beam will involve a huge demolishment and a possible weakening of the whole support structure? 2/Is it possible, as the plumber has claimed, that the leak will eventually seal itself off as residue from soap etc collects on the inside of the PVC pipe? There is no calcium in the water supply (cistern water) so I cannot rely on this. The builder has gone bust and I am left holding the can on this one without a clue about what to do.

Ouch. Sounds like your in a tough spot. As Im sure you know, the only way to do this correctly is to gain access to the leaking area, and fix it correctly by replacing the leaking area. Or gaining access to the upper and lower portion and rerouting the pipe. Somebody made a big boo boo. Fist off, the pipe should not have been poured directly in the concrete (or was it, you say it is blocks, so they may be able to break out some blocks, and replace the blocks without any major sturctural damage?), it should have been sleeved. Second, this leak should have been found during testing of the plumbing drainage/venting system. The fact that the builder went bust, makes this extremely hard on you. The fact that the plumber says it will seal itself, only says to me that your plumber should not be allowed to do plumbing. I hate to say it, and almost never will, but I think you may have a ligitimate lawsuit on your hands. Somebody needs to make this right, and it shouldn't cost you a dime. I certainly hope you had a licensed contractor do the work, and I hope he hired licensed subs, otherwise this could be a real nitemare for you. Good luck, and please let us know how things turn out.

I would like to know what the leaking pipe feeds. You may really have a chance of rerouting the pipe. It may mean building a small chase, but much better than tearing into that concrete support beam.

One last thought. These things do happen. Give the plumber a chance to make it right. But, if he just isn't willing to make things right, and correctly, or you find that the cuase of the leak is not the plumbers fualt, but is the long gone builders fualt, then you need to decide if you want to get someone else in there to get the job done, at your cost, or if you want to go through a lengthy court decision. This really is a tough one. Wishing you the best.

Many many thanks for your answer as I feel totally isolated on this one. I should explain that I am resident in Belize(ex New Zealand)! Legals, here? Forget it, it ain't going to happen. The reinforced beam was totally poured (I think it is part of what they call here "the chain") it contains the drainage line from the upstairs kitchen and shower areas and I don't think that any thought was given to the processes for totally encasing a PVC pipe in concrete. I guess I was hoping for a xmas miracle along the lines of adding compounds to a radiator to stop leaks in the hose. Better to know the reality of the situation than relying on mis-information. Thanks again for your prompt response.

Oh wow, sorry. Only thing I can think of is to get in someone else to see if they can't reroute the line. Does that seem like it might be possible? Hard for me to really give much advice without seeing the exact layout.

What size is the pipe that is in the concrete? It may be possible to have it lined, however, Im not even sure it that's an option in your area (if anybody even does it there). I really wish I had an easy fix here. I would love to be that Chirstmas miracle, but sadly, Im not. Do keep me posted on your finding though. Always curious to see how these things turn out.

I take a dim view on a leak repairing itself. How large a leak are we talking about? If just a small drip once in a while grease and build up may cover and contain the leak but if it pours out when you drain I can see only one option open to you.
Cutting into the supporting beam is off the table. The line will have to be discontinued and a new line run. Along with MGD I wish you good luck and please keep us informed. Good luck, Tom