Little bedroom's ceiling is infested with moulds

28 Aug 2015
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South Wales
United Kingdom
Our little bedroom (3.2m x 2.8m) ceiling has tiny black dots in patches by the external wall. I can see they are moulds and spreading fast.

Which anti mould ceiling paint do you guys recommend us to buy? I have already read so many positive and bad reviews on Dulux Bathroom+, Ronseal 6 year anti mould white matt, Zinsser Self-Priming Paint white and many others. Based on your experiences, which ones did you use and whether they were good?

I need one that has a low odour and quite thick and drys within 1-2 hours for the second coat.

Your advices would be appreciated :)
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Forgot to mention. The adjacent wall (also external) is beginning to develop black moulds too.
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I recommend you open the window more often.

Is wet washing draped around your home?
Have you got trickle vents on the window (s) in there ? If so open them if but might be good idea to fit one :) we had similar issue due to the nature of the building needed ventilation.

Once sorted the condensation use a stain block paint / spray then coat with normal emulsion
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Ventilation ventilation ventilation!

Once you have cured the problem, then you can cover and repaint the walls.

The PVC window does not have tickle vents at all. We open it during the day but not at night and we dont dry clothes in that bedroom.

What is a stain block paint/ spray?

Is it a good idea to cover all walls with hygienic white PVC panels and anti-mould matt for ceiling?
Also we leave the door ajar all day long and both bathroom and kitchen which cause steams and condensations are nowhere near this bedroom..
Black spot mould is indicative of condensation related issues.
As has been said, address the lack of insulation and ventilation. Job done.
Damp air will circulate throughout your home so the bathroom and kitchen need extraction to remove it. If anyone sleeps in this room they will be exuding water by breathing and perspiring.

If wet clothes are draped in any part of your home, your home will be damp.
I would fit trickle vent in room that will help reduce the condensation also check up the attic where the mould on the ceiling is to see if there's any insulation. Might be a cold bridge between warm air in bedroom then the cold air in the attic. Insulate that, fit a vent, get this or something similar

Let dry then paint over

I had exact same issue in our front bedroom doing this cured it :)
It is definitely a cold bridge. The mould is forming at the most vulnerable spot i.e. at the lowest point at the eaves. Think about it. The external roof/ceiling/wall abutment is where the roof is at its lowest in relation to the ceiling and where there is the least protection.
Do not open the windows, this is very bad advice and BS5250 is very clear on effective methods of ventilation, opening windows is not one of them! Ventilation has to be carefully managed. Ventilation is important but its not everything, it's simply a potential factor that needs addressing. It would be useful if you could explain the construction type. Have you got solid walls? Are the bedrooms partially in the roof space so you have poorly insulated ceiling fillets? Have you got double glazing. Have you got a fully controllable heating system installed? What about occupancy? How many people live in the house and how many bedrooms are there? You may find this blog useful...
Lol. Try the basics /cheapest like I have mentioned before going beyond that. If you notice a reduced amount of condensation then continue with my advice as its been a godsend in our house :)

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