Damp mark on plasterwork

[kirky1176]

Hi All,

I recently discovered that the plaster work in the corner of my lounge was damp. The corner is an exterior wall. There is no mould or growths, just a slight discolouration that happens when plasterwork gets wet.

The patch only appears in one corner and runs from the skirting up the two walls that make the corner about 10"s and out from the corner about the same. There are no other patches in the room.

The house is fully rendered - not sure on the material as it was done before we moved in. On the corner of the house where the damp is, the render appears to be detached from the wall i.e. knocking on it sounds hollow.

I'm making a guess that if there is a gap between the render and the brickwork (above the camp proof course), then water/condensation could be stuck in the gap space and gradually seep through the wall?

Reasonable explanation or is there something more sinister at work? House is 1950s if that helps.

Appreciate any thoughts and where I might got for some good, professional advice.

Thanks.
Mark

 

[HERTS P&D]

What is the state of the guttering outside this section of wall? any leaking joints?

Post some pictures of inside and outside of the problem.

Andy

 

[kirky1176]

Hey Andy,

Thanks for the reply. The gutters are ok, although we have just had them cleared and the chap that cleared them did say they were a little 'full' so could be a potential cause.

Images below. Hope they come out OK.

View media item 40145 View media item 40144
Thanks,
Mark

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[HERTS P&D]

Get a desk fan and aim it at the damp on the inside, it will soon dry out and now that the gutters have been cleaned out, I would see if it comes back.

Andy

 

[ianblue]

If the rendering is "blown" as you say it would pay in the long term to have it repaired.
Being a fifties house it should have cavity walls. The idea being that even if the outer leaf gets wet the internal leaf should stay dry. Also a fifties house would have a damp proof course.
There are ties between the outer and inner and if they have not been put in properly moisture can travel across, also careless brickies can fill the cavity at the bottom by dropping mortar while buiding.
Condensation is another possibility ofcourse.
Hope I have given you some pointers.
Good luck