Damp patch on boxwork

[IainH1]

Excuse the long-winded entry but you'll see why...
Our house is 12 years old and we moved into it in Summer 2004. The main soil pipe descends from the bathroom behind some boxwork in the corner of the dining room below. In July we discovered a leak where the bath waste pipe enters the soil pipe which we had fixed - this was discovered when we found a damp carpet and base of wall at the bottom of the boxwork. This has now dried out and all was good.
Last night a damp patch about 6-8 inches square suddenly appeared on 1 side of the boxwork wall about 3 feet up - the painted plaster was slightly damp to the touch.
Being completely naive about all things structural, what could possibly have caused this to suddenly appear, especially where it is, and given that there are absolutely no other signs of a leak?
Could it be a case of the plaster being damp inside the boxwork from our original leak and now the damp is being drawn out with the heating being on and the doors and windows being closed?
If I need to call someone out to investigate who do I call? Builder? Joiner?Plumber? Surveyor? Insurance company?
We had the cavity walls filled earlier in the summer but this should not have affected the boxwork at all - or could it? Do I add Cavity Wall company to the list above?

 

[joe-90]

I think the most likely cause is a recurring leak from before. If it leaked once it can leak twice.

The reason it is showing up where it is, is probably because there is a reinforcing batten to hold the boxwork up and the water is dripping onto it.


joe

 

[Softus]

Get a recommendation for a builder from a trustworthy friend or colleague, and call them in. A competent one should tell you that they can't identify the cause of the damp without at least seeing the damp patch, and probably not without opening up the boxwork - for this reason you shouldn't call in someone like joe-90 who will offer a likely cause without even seeing the problem.

 

[joe-90]

What's your problem? I can't see the house. I can only post on what is written. Why are you following me all over the forum talking nonsense?

Any fool can say 'get a builder in' the poster doesn't need anyone to say that, after all, what use is it to him? He KNOWS he can call a builder in. What he wants (at his time) is to get ideas on what might be happening behind the boxing.

If you are going post - at least make it helpful to the poster.


joe

 

[Softus]

What's your problem? I can't see the house. I can only post on what is written. Why are you following me all over the forum talking nonsense?

Um, but you didn't, did you. And I'm not.

Any fool can say 'get a builder in' the poster doesn't need anyone to say that, after all, what use is it to him? He KNOWS he can call a builder in. What he wants (at his time) is to get ideas on what might be happening behind the boxing.

If you are going post - at least make it helpful to the poster.

...who do I call...?

You didn't answer the poster's question joe. I did. Given that you didn't read the post properly, I'm quite surprised you didn't tell him to replace the flow switch solenoid dongle bush.

 

[IainH1]

Hope you two have kissed and made up....

I have traced the problem to a leak - not the same joint as before but another one... in process of getting fixed and dried out again.

Thanks anyway for your time.

 

[Softus]

Thanks anyway for your time.

Glad you found the problem!