Annoying damp external wall!!

[Ellie2000xx]

Hi all
I've recently renovated an old semi detatched house. The internal walls have been plastered. My problem is, one of the walls (external) is plaquing us with mould in very specific areas. We have taken a few bricks out an emptied the cavity (which was blocked with old motar) and rebricked them, this didn't work. We then took the bottom course of bricks out, put new damp course under them an rebricked, that didn't work. In the process, we also had our inside floor renewed, new damp course, insulation and screed. The plasterer cut out a problematic area on the plaster, re boarded an plastered, problem is still there. I was then told to PVA the wall, which I have now done, but there is still little "flowers" of mould coming back!! It might be of interest, the wall use to be an old coal house wall, if that helps??!!
PLEASE HELP!!!

 

[joe-90]

A piccie helps a lot.

 

[Ellie2000xx]

Will put a pic on in the morning. Can't upload them from my iPhone lol

 

[peterperfection]

Hi all
I've recently renovated an old semi detatched house. The internal walls have been plastered. My problem is, one of the walls (external) is plaquing us with mould in very specific areas. We have taken a few bricks out an emptied the cavity (which was blocked with old motar) and rebricked them, this didn't work. We then took the bottom course of bricks out, put new damp course under them an rebricked, that didn't work. In the process, we also had our inside floor renewed, new damp course, insulation and screed. The plasterer cut out a problematic area on the plaster, re boarded an plastered, problem is still there. I was then told to PVA the wall, which I have now done, but there is still little "flowers" of mould coming back!! It might be of interest, the wall use to be an old coal house wall, if that helps??!!
PLEASE HELP!!!

Like Joe 90 says- a pic is needed.
Coal houses are usually single skin (Half Brick) walls--unless they are part of the main building .
How old is the house ?.
Is there any ventilation in the affected room ?.
Is it the coldest room in the house ?.

 

[Ellie2000xx]

It's an old house, prob 30's. The coal house is part of the main building, but I mentioned it cos it didn't have a proper door into it, an it was accessed from outside etc. plus very dirty in there.
There is good ventilation in the room, it's my living room, but the house is empty at the moment, but I am putting the CH on every other day for a good few hours on the cold days.
Will upload a pic now
Thanks

 

[Ellie2000xx]

I only recently cleaned the wall inside, so you dont get the full effect of the mould.

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• Ellie2000xx
• 19 Aug 2012
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• Ellie2000xx
• 19 Aug 2012
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• Ellie2000xx
• 19 Aug 2012
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• Ellie2000xx
• 19 Aug 2012
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• Ellie2000xx
• 19 Aug 2012
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• Ellie2000xx
• 19 Aug 2012
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[EB1caneyeB]

I can't really work anything out from the pics (must be my eyes).

Are there air bricks. If it once was an open access cupboard it wouldn't have need for them. Soon as you've put a door on the cavity will need air flow.

I can't work out how big the area is that is a problem. But it would be worth putting a couple of air bricks in. The course below the Damp course would be ideal. Failing that the course above damp course. Any spoil in the cavaity should be removed to at at least three inches below damp course.

 

[Ellie2000xx]

There is 1 air brick, but i may put another 1 in, but would have to put it about 2 courses above the damp course, would this be ok? Do you think it would solve my problem?

 

[EB1caneyeB]

is the cavity clear at damp course level ? Quite often with old buildings you get snots (excess mortar) from the back of brickwork and debris filling the cavity to a level higher than the damp course. This must be clear. Preferably 150mm lower or at least 75mm lower than the damp course.
When you opened up the brickwork could you smell that damp smell ?

Were the walls cleaned thoroughly ? Is the staining from soot bleeding through ?

Another air brick would help i think. I don't know if it will cure this prob for you though.