Painting a mouldy ceiling?

[SRJDIY]

Hi all. I have a patch of mould on my bathroom ceiling that I want to get rid of and prevent coming back. However, there's a few things I'm not sure about.

I'm planning on doing the following:

1.) Cleaning off the existing mould with an anti-mould spray
2.) Applying a stain sealer to stop any remaining stains showing through
3.) Painting the ceiling with a mould-resistant paint

However, the wall is covered in plastic cladding, with what looks like hard grout where it meets the ceiling (see attached picture). Is it best to remove/treat the grouting before painting the ceiling? I'm concerned that if I paint first, then dealing with the grouting might mess with the paint job. Also, does it look like the grouting would need replacing entirely, or can it be treated with one of those grout refresher pens? I'm not sure how well they work.

Also, can certain paints only be used over certain types of stain sealer? I've seen Zinsser BIN and Zinsser bullseye 123 recommended as stain sealers; apparently one is shellac-based and one is water-based, but I'm not sure what that means when it comes to painting over them. Also, can you apply stain sealer over just the area with stains, or do you have to cover the whole ceiling with it to avoid it showing through the paint?

And one final newbie question - whats the best way to clean stain sealer off your brushes/roller? I'm assuming water if it's water based and white spirit if it's not?

Thanks for reading all of this and for any advice you can offer!

 

[JohnD]

Hi all. I have a patch of mould on my bathroom ceiling that I want to get rid of and prevent coming back.

then you have to cure the damp that causes it. paint will not cure damp.

how and when do you ventilate the room?

 

[SRJDIY]

then you have to cure the damp that causes it. paint will not cure damp.

how and when do you ventilate the room?

The house used to be a rented property, and the extractor fan was only upgraded to be powerful enugh for this sized room a couple of years ago. I suspect that mould formed previously due to excess humidity and the tenant or landlord just painted over it without actually removing it, which is why it's coming back now. Now there's a proper fan, I'm assuming that if we kill the mould off and use a proper anti-mould paint that will resolve the issue.

The extractor fan comes on when either the light is turned on and remains on until around 5 mins after the light is turned off. This means it is always on when someone is in the shower. We also make sure to keep the window open when we shower, and there is also a slight gap under the bathroom door.

 

[JohnD]

please show us a pic of your fan. they vary.

5 mins overrun is unlikely to be enough.

the fan will be more effective if the window is shut (if the fan is adequately powerful)