Mouldy flaky walls in bathroom

cormie

Hey folks,

Just looking for advice on how best to manage this! It's in a bathroom and the flash has brightened it, but the mould is pretty black around the window recess. I think what's flaking off is paint and then it's just plaster directly beneath. You can also see some cracking on the wall to the left if you zoom in.

Would it be ok just bleach the area, then sand it back to mould free paint and then give a fresh coat over bare plaster and continue then over the whole room? I've seen recommendations for Zinsser Permawhite Mould Resistant Paint. Would this be enough, or would I need a primer or some other undercoat first on the plaster?

There's also a radiator that has some rust specks like this:

It's not as bad as the above, just smaller specs towards the bottom, but the radiator is a little dirty too.

Would I need specific radiator paint here, or any other advice? Any chance I could use the same paint for the walls, ceiling and radiator in this bathroom?

Any advice would be great!! :)

10-10-20

For that rad, I had some good results with Hammerite radiator spray, but frankly those steel rads are very prone to rusting if they get splashed frequently, especially with "yellow water".

Take off the top-cover and two side covers (they clip off if you pull at them). Wash them and the radiator, etc. Sand it down well and clean it off as recommended, then cover the floor and walls with paper. The mist from the spray travels, so just keep the door closed and cover anything within 1.5m. Three coats will give good protection.

For the window reveal, I think you're always going to have this battle on your hands as the cold is coming down from the inner cavity and landing on the reveals. This cold attracts the moisture which the mold live off. Only removing and insulating the reveals will provide a complete fix. But for the moment I would recommend using a mold remover spray and then a mold resistant paint or a good quality bathroom paint. But as I said, it will be back.

cormie

Hey that's very helpful, thanks a lot for your input! I might look for something similar to the spray in a brush on form as overspray can be a pain in the ass to deal with! Thankfully the radiator in the image above is just one I found online and the one I've to deal with isn't as bad.

With regards the window, I think I'm just going to keep this window constantly ajar and hopefully that'll help, a cold bathroom is preferable over a mouldy bathroom in my books :) I'll probably try get that Zinsser Permawhite Mould Resistant Paint and just get a remover spray at it first, then sand the flakes back and then paint over the whole thing!

Lumen

Careful use of open window and dehumidier has kept mould at bay in my bathroom.

The way I use is as follows:

• Open window and turn dehumidifer to high before and during shower
• Before leaving the bathroom, close window and turn dehumidifer to low
• Come back a few minutes later and turn dehumidifer off.

Although it seems mad to run a dehumidifer with an open window it works out more efficient (i.e. the dehumidifer runs for less time overall for the same effect). I have tried many permutations!

I have no extract ventilation btw.

cormie

Thanks Lumen! Why would you close the window though? Just to keep the heat in?

Lumen

https://www.boards.ie/discussion/comment/118137083#Comment_118137083

With the window open in the winter it never gets properly dry - the air cools down and the walls don't quite dry out completely. That few minutes with the dehumidifier on low and the window closed just seems to leave it nice and warm and dry.

This is only in approx Oct-Mar though, in "summer" the window is left open and the dehumidifier off.

This is a dessicant dehumidifier which also warms the room nicely.

cormie

I would have thought as long as there's fresh air circulation through the window in the bathroom it'd stay ok no matter what the season? I'll need to test it out. Got away with just 1L of that Zinnser Permawhite anyway :)

Lumen

https://www.boards.ie/discussion/comment/118141048#Comment_118141048

Well yeah, but if you never close the window you effectively have an outdoor bathroom!

10-10-20

Because spiders.

Enough said.

loyatemu

just to follow up on the question about Zinsser Permawhite. I painted our bathroom ceiling with it after cleaning off a load of mould. The mould has not returned at all, except on a few bits around the edge where I clearly didn't get enough paint into the corners. So it works well. I had previously had the walls redone with some other variety of supposedly mould resistant paint - they are still getting mouldy though at least it's wipable. I'm tempted to do the whole room in Zinsser.

Bathroom has a window and an extractor fan, still goes mouldy - it's a never ending battle (particularly with kids who don't open the window and have half-hour showers).

cormie

Thanks for the input! That's good to hear, I gave the problem area a few coats and took it back right to the plaster so hopefully no spores remained and with my "outdoor bathroom" set up, spiders and all, I'm hoping not to see any mould appear. I'm not sure what the previous occupier was doing to get it as bad as it got, but hopefully all the wrong things!