Black Mould

[Worried74]

Hi, struggling with black mould in a bathroom and bedroom. Now have dehumidifiers in place. I have tried removing but it always comes back and is more vigorous than before. Desperate to remove and decorate. Any tips? If I can remove should the area be sealed with anything before painting?

Keep the area as dry as possible (eg open the bathroom window to air after showering)
You can get anti-condensation paint which had worked for the most part on our ceiling.
Otherwise bleach spray as soon as you see the first signs.

I regulary had this problem in my old bathroom and removed it from the white painted ceiling with an old toothbrush dipped in bleach. Bleach spray also helps.

Dry home, well ventilated is what keeps it away.

Ventilate and anti mould paint. Bathrooms paint is usually anti mould. It's more expensive but it does help.

Must be cold surfaces, try to keep the humidity down as much as possible, decent extraction and try to keep the rooms reasonably heated as well especially bathroom.
The ultimate solution is to insulate but I'm imagining that's not the short term.
Ironically all the bathroom paints and other impervious coatings can exacerbate the problem. Plaster and timber acts as a humidity buffer during short period of high humidity eg showering, preventing the water running down the walls.
Another tip is get a decent squeegee to wipe the water off the walls and tray after showering. We use the one you get for doing cars as it's got a longer blade.

For the bathroom fit a good quality humidistatic extractor fan, and open the window when showering/bathing. Make sure the room is properly heated and dries out quickly after use, if it's dry the mould won't grow.

You say you have mould in a bedroom too, whereabouts? Wall, ceiling, around a window? Again making sure it's properly ventilated and kept dry is key, opening windows in the morning and wiping away condensation from Windows will help. But as bedrooms aren't as damp as a bathrooms you may need to look for other sources of moisture such as a leaky roof or gutter etc.

You need an extractor fan, that works.

Every inch of air in the world contains mould spores. You don't prevent it happening by removing it. You do it by removing the warm, damp conditions that encourage it to grow.