Black Mould

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This has been a problem for a while and although i've tried using chemical assault and wiping down, nothing shifted it. So, after a morning spent dismantling the old brown wardrobe in front of the wall (yeah, i know) to give me room for taking off the plaster altogether and replastering.
Is there something i can spray or brush onto the underlying brick to help prevent it returning?
Or do i have a larger problem, as the wall is a gable end, upstairs, above a room where the wall is always cool in summer and bloody cold in winter.

View attachment 271797
 
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If there is a wardrobe in that corner, I suspect that it is the result of a lack of airflow.

Might you be able to dot and dab insulated plasterboard.
 
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OP,
Why not remove the paper from both walls and post pics of what you expose? Pics of the outside of either wall would also help?
What floor is this on - gf, Ff etc? Is the wall cavity or solid?
 
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If there is a wardrobe in that corner, I suspect that it is the result of a lack of airflow.

Might you be able to dot and dab insulated plasterboard.

OP,
Why not remove the paper from both walls and post pics of what you expose? Pics of the outside of either wall would also help?
What floor is this on - gf, Ff etc? Is the wall cavity or solid?
I've removed the wardrobe (despite vigorous protests from Herself) and intend to make shelves along the wall with an easily moved cabinet alongside, hoping to create a space with better airflow - insulated plasterboard sounds like a good idea: how far up the wall beyond the height of the mould should i take out to ensure complete success?

The wall isn't papered, just painted, and is a cavity wall, first floor room. I'll get round to posting pics after i've finished clearing up; it looks like a jumble sale up here!
 
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If you keep doing the same thing then you will get the same results: so: no shelves, no cabinet or anything else.
There's a few ripples in the plaster which suggested paper. However the safest, long term thing to do is hack off all plaster 300mm beyond any condensation signs and use a sand and lime render to re-plaster so to speak.
Do you have CWI?
 
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If you keep doing the same thing then you will get the same results: so: no shelves, no cabinet or anything else.
There's a few ripples in the plaster which suggested paper. However the safest, long term thing to do is hack off all plaster 300mm beyond any condensation signs and use a sand and lime render to re-plaster so to speak.
Do you have CWI?
You recommend leaving the wall bare? i'd like to wallpaper on top.
I've no idea what CWI is so i couldn't say if it's there or not.
Here's a pic of the outer wall. It looks okay but i don't have a ladder long enough to go up there for a closer inspection.
IMGP5437.JPG
IMGP5437.JPG
 
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I recommended using S&L render as in post # 5. And to leave the corner free from furniture.
After a couple of weeks for drying then paint - dont use wallpaper.

Render has been applied to both exterior walls - typically, render is often applied to older property with solid walls in order to protect it from damp penetration. Judging by the eaves, your property is pre-1914.
I'd suspect that your walls are solid walls?
The finish on the RH rendered wall is poor - plus the metal corner bead is rusting.
If you do have cavity walls with CWI - the CWI might have failed and be damp or even soaked?

Pics showing the bottom of the walls at ground level might give a little more info?
 
D

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Back to plaster and bond insulated pb to it then skim.
if the plaster is rotten chop it off back to brick and bond insulated pb to the brick then skim.
In any event lime render is not the answer on an internal cavity wall, especially if you have cavity wall insulation that’s damp or wet.
 
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You recommend leaving the wall bare? i'd like to wallpaper on top.
I've no idea what CWI is so i couldn't say if it's there or not.
Here's a pic of the outer wall. It looks okay but i don't have a ladder long enough to go up there for a closer inspection.
View attachment 271814 View attachment 271814
Black mould only forms on the cleanest of water, which means it is almost certainly condensation

Bond some insulation onto the wall behind the shelves you are going to put up - leave the bedroom door open during the night to let the air circulate better whilst you are sleeping.


Two people asleep could be breathing out the best part of a litre of water per night -
 
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Well, the consensus seems to be: insulated plasterboard; skim, dry out and keep clear. No wallpaper and adequate ventilation. All this has been very helpful and it's clear to me that i need professional help on this one...i'm just not that handy with this kind of job.
 
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After two wildly different appraisals by a couple of local plasterers i've decided to bite the bullet and do it myself. The last bloke wanted to take off the plaster from the corner right across the wallo_O The advice i've recieved here sounds much more sensible.
 
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If there is mould on wall then there is moisture on wall. The moisture could come from outside, or the moisture is caused by warm air contacting a very cold wall producing condensation. You can kill mould using bleach. But this doesn't cure the cause of a damp wall. Once the bleach wears out, the mould comes back.
 
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What thickness insulated plasterboard is required on something like this?

Plus is it beneficial to put some sort of barrier onto the bare brick after plaster/cement has been hacked off?

Thanks.
 

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