Help........... Flaky / Damp ?? Interior Wall

20 Dec 2005
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United Kingdom
Hi all..............I have an extension where one of the interior walls, which faces north on the outside, is rendered.

Since it was completed by the builder a couple of years ago, the interior plaster has been gradually flaking away ( bubbling in parts) and when you rub it the whole area just crumbles back to the block work.

I am assuming ( perhaps incorrectly) that the damp from the outside wall is penetrating through and ruining the interior paint on the wall. I have central heating in the room so it is not cold in any way and its just its just this one wall.

I had painted the inside with a damproof paint but that too has now broken down in parts. Can anyone suggest how I might over come the problem.

I had thought of covering it with thin polystyrene roll, but I don't want to do that if there is an easy and better remedy.

Many thanks in anticipation and a very Merry Christmas to you all..... Sincere regards................Pete
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You really need to sort the damp source pete...dont waste your hard earned on covering it up until you find out why its blowing.
Hi Zampa...

Many thanks for our reply. The deterioration on the inside of the wall starts at the top and spreads downwards? On the outside of the wall are some block/paving steps positioned on the right hand side of the wall as you look at it and these lead upwards to a raised doorway.

This gives a triangular shape to the outside of the wall. As stated, it is all north facing and I am beginning to think that, when it rains and then lays on the steps until it drys out, maybe this water/ dampness is seeping through the outside wall to the inner and creating the 'breakdown of the inner wall's surface? Is that a possibility?

Any ideas on a tried and tested product that I might be able to use on the outside wall, that would assist in preventing the possibility of penetrating rainwater or, any suggestion as to how I might be able to proof that bit of the outside wall, would be extremely helpful.

Once again many thanks a a Very Merry Christmas to you and yours - Pete
Sponsored Links no builder (ask the mrs!) but can I assume that a part of the wall inside is below ground level outside?...

If that is the case you need to dig it away and apply a few coats of bitumen.

Work on the source until its sorted...doing anything inside will be a waste at this stage.

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