Strange damp pattern

[desertrose]

Hi all,

Because of this damp, about a month ago I had a problem with the internal soil pipe to clay drain connection diagnosed - there was also damp around the soil pipe inside the property - and repaired (joint dug out and completely replaced). This is where the new paving slab is.

I was told this would fix the problem but a month later and I don't think the wall is any less damp. Some days it looks more damp than others but I can't work out the pattern (e.g. doesn't seem related to rainfall - this photo was taken yesterday and it hasn't rained for days, although it was a fairly damp frosty morning). Water (including supply pipe) and drainage are all in this area but everything (now) looks dry on the inside of the property.

I'm at a bit of a loss where to go next with diagnosis so would appreciate any thoughts on what might be happening here. Many thanks in advance!

 

[^woody^]

Damp insulation? Cavity blocked?

 

[desertrose]

Thanks ^woody^! Quite possibly - the walls are indeed insulated - the white fluffy stuff rather than the beads.

Was it optimistic to think this might have all dried out in the month after the source of water was eradicated?

The drainage people said it'd be dry in a few days, but it honestly looks as wet now as it did then, especially in the morning.

 

[HERTS P&D]

Get a carpenters pencil and draw around the edge, then see if it has got bigger or smaller after 10 days.

That way you will know if there still is a leaking pipe/joint.

Andy

 

[desertrose]

Thanks Andy; good idea. In the meantime, this photo pre-drainage repair is maybe a useful comparison:

Other than the mortar covering the DPC having dried out a bit, they look pretty similar to my eyes, unfortunately.

 

[catlad]

Knock a brick out and see what's going on.

 

[HERTS P&D]

I think it looks wetter now.

Do the pencil test and take it from there.

Andy

 

[desertrose]

Thanks to everyone for your helpful replies. It's been over a month since the repair now and the wall is currently looking fairly dry. Quite a difference to last weekend (above).

 

[JohnD]

you might find you get a lime bloom appearing as it dries out. In my district, garden walls and new-ish builds have been showing in the last week after the sun gets on them. It will weather off.