Paint not drying/Damp

[matt86]

Hi,

I have recently painted a room. Under the window there is a area of paint that has not/will not dry. The rest of the room is fine.

I think as the area under the window is very cold (ans possible damp) the paint will not dry. I have re done a bit of pointing and sealed the brickwork outside so there should be no problem with water getting in from outside and i have checked under the floor boards and that is bone dry so no worry of interfering rising damp.

I think as its the only section of wall that is 'external' in the room its condensation thats making the wall slightly wet/freezing cold.

Would i be best to install a dehumifier to dry our with this and addition of heat or wold i be best to strip paint back and undercoat with anti damp undercoat? My worry being that this undercoat won't dry?

Has anyone ever had similar issues or any idea that i can try?

Thanks in advance!

 

[opps]

To test to see if it is indeed condensation, get a large piece of bacofoil and tape it to the section of the wall. If condensation, the room side will be damp.

If the other side is damp then it might be a sign of earlier ingress from outside. Even though you have repointed the wall could still be damp. mind you, if the paint still hasn't dried the wall side of the foil will be damp regardless.

If the wet paint is indeed the result of earlier ingress just leave it as it is. Matt paints will allow the moisture to evaporate, albeit at a lower rate than a paint free wall. Stain blockers will make it more difficult for the wall to dry.

Drilling a series of holes in the plaster will help dry the plaster if necessary.

It might also be advisable to check the exterior window cill for hairline cracks

heating and a dehumidifier will help