Boring question about drying out a damp wall

[Coconutfeet]

We recently moved into a house with a damp patch on an upstairs wall caused by a leaky gutter. The gutter has now been fixed but the wall was really wet where the water had been pouring down it. I've keeping the windows open as much as possible and putting the dehumidifier on and, about 6 weeks on, it now feels dry to the touch.
In order to see whether it's dry enough to replaster, we're presumably going to have to hack the plaster off. The wall is in ds's bedroom and someone I was talking to suggested that he may not be able to sleep in there once we'd done this. It appears to be a patch less than a metre squared and I had thought that as long as it was well-cleaned it would be ok. Any ideas why it wouldn't be?

Also how long should it take to dry once the plaster is off? Is there anything else I can do to dry it out faster?

I don't see why you need to replaster unless the surface is badly damaged. You normally take the plaster off to help it dry quicker.

But if it's dry and the source of the leak is fixed rub surface down, Fungal wash it, and then paint.

I think we will need to replaster as it's really crumbly where it was wet.

Can anyone help?

Don't run the dehumidifier with the windows open, or it will try to dehumidify the world,

If you have the windows open, put a fan blowing on the damp wall (not a fan heater). The airflow will evaporate the water, and the open window will let it out.

Wet walls are said to dry out at the rate of about one inch (depth) per month.

If you are going to replaster, the sooner you take the old plaster off the better as the brick will dry faster.

"someone I was talking to suggested that he may not be able to sleep in there once we'd done this"

I wonder what they were talking about?

Hacking off plaster is dusty work so empty the room first. Brushing the exposed wall with a stiff broom will take off the loose dust, and hoovering with a canister vac (not a household one as the dust will damage it) will clean it up. I find the dust quite irritant.

To prevent the exposed wall releasing dust you could give it a coat of dilute PVA which will seal the surface (note: never put PVA on any surface which you hope one day to paint, such as finished plaster) and tell the plasterer you have done it.

PigletJohn - i forgot & left the window open the other day with it on - not a clever idea in humid wet wales!

at dehumidifying the world. Thanks Pigletjohn. Very helpful as usual! Will get to it now.