On Monday, 16 April 2018 14:44:05 UTC+1, Pagw wrote:

Hello, I unfortunately discovered a leak behind the sink in one of my
bathrooms the other day. The water has had time to soak the floor where it
couldn't be seen and also flow to an adjacent bedroom under an interior wall.
Black mould has grown on the floor of both rooms up to a couple of feet from
where the leak occurred. I'm now letting the floorboards dry out and have had
a go at removing the mould using bleach, vinegar and a mould remover product.
However, I've managed to get rid of half of it at best so far, and the black
stain seems to go beneath the surface of the wooden boards (which look to be
made of chipboard, and they still seem structurally strong). Additionally, the
mould in the bathroom is in difficult-to-reach places - inside a wooden
enclosure for the pipes behind the sink and between the bathtub and the wall.
I think removing it fully will require taking all of this apart.

I was wondering how necessary is it to remove all of the mould? Would it be
sufficient to dry out the affected areas so that the mould would become
inactive? We only use the bathroom in question for toileting and using the
sink, so it doesn't get very humid and has never required any effort to keep
mould at bay before.

Also, should I be concerned about the wall between the bathroom and bedroom? I
can see signs of water ingress reaching just above the skirting board in the
bedroom.

Thanks in advance for any help.

Black mould is too toxic for it to be a good idea to leave it there. Bleach is the stuff to use. Apply & leave. Repeat daily until it's gone, which will take several goes. Doing this on chipboard may ruin it though. Many people remove all mouldered material & make good on grounds of toxicity.


NT