Moldy ceiling

[avisccs]

Hi all

My extension ceiling has been leaking for a year. The flat roof has been recently fixed (new felt). A part of the ceiling is moldy. An area of about 2 meter x 0.2 meter is moldy. It is right at the middle of the ceiling where is lowest point. I don't know whether this affects the other part of the ceiling without look at this internally. Currently, the ceiling has wall paper on it. When I poke the ceiling, all the plaster boards seem to be solid.

Please give me some suggestions on how to fix this? Do I need to take the plaster board off to assess the internal? Would the mold die eventually because of the low humidity? Can I just treat the surface of the ceiling (i.e. take wall paper off and skim it with thin layer of plaster)?

 

[NickB_99]

Hi all

My extension ceiling has been leaking for a year. The flat roof has been recently fixed (new felt). A part of the ceiling is moldy. An area of about 2 meter x 0.2 meter is moldy. It is right at the middle of the ceiling where is lowest point. I don't know whether this affects the other part of the ceiling without look at this internally. Currently, the ceiling has wall paper on it. When I poke the ceiling, all the plaster boards seem to be solid.

Please give me some suggestions on how to fix this? Do I need to take the plaster board off to assess the internal? Would the mold die eventually because of the low humidity? Can I just treat the surface of the ceiling (i.e. take wall paper off and skim it with thin layer of plaster)?

Given you have stopped the source of water, that's good!
Mould on the surface should only need to be addressed with a suitable wipe down (mild bleach etc) and possibly applying paint with some blocking properties.
Given it's wallpapered though, I'm not sure if you were planning to paint it all....

However, above the boards -
Obviously good that the plaster board seems solid, my concern would be if the joists have sustained some damp damage from sitting in water for a significant time.
Drying damp wood out can cause problems with rot later. You may only know this if a plasterboard or two is cut in the area and you have a look. If the damage is not too bad, you may be able to treat with a suitable product e.g. http://www.cuprinol.co.uk/products/5_star_complete_wood_treatment_(wb).jsp
Then re-do boards and patch in.
Only 0.2m wide sounds like most of the water sitting along a single joist.

You may just get away with tidying up the mould on the outside - difficult to be sure.
Or call in the home insurance and they could sort it all.

Pros may offer more advice from their much more extensive experience. You may also get more feedback if you ask the mods to transfer to the Roof section of the forum - don't duplicate posts!