Condensation mould in bathroom

ey_up

Hi all,

Please could someone help with my ongoing problem with mould due to condensation in our bathroom. I have a small bathroom, 2m x 1.7m. with shower, separate bath and sink. floor is carpeted, walls tiled and ceiling papered and painted with mould reducing paint. There are two double glazed windows, one north elevation and one east so the room does not pick up any sun. We have an in line extractor venting to the outside and also open the windows to reduce moisture as much as possible following showers typically in the morning.

My problem is the north eastern corner ceiling, maybe 300mm square area that remains damp and eventually grow black mould and the paper bubbles away from the ceiling. I have insulated the loft with kingspan, approx 100mm depth above in the loft but for this small corner which I cannot access because of the timber rafters purlins, ceiling joists etc. I know I have a cold spot but what can I do to prevent this if I can't get access to put in insulation? Would some expanding foam do the job or create more problems?

I am getting tired of cleaning and repainting the area to last only a month or so before mould returns.

Any ideas much appreciated.

Thank you

phil24_7

Take a bit of the ceiling down, insert insulation, put ceiling back up?

martinsurrey

https://www.ipsluk.co.uk/aquaclad-classico-white-gloss-3m.html

I'll never go back to painted bathroom ceilings again, easy to solo fit, £15 per sq meter, 3 years in an internal bathroom and I've not had to do more than wipe them.

phil24_7

But this will only hide the problem, not solve it!

bobbymotors

spray it with hg mould spray, about £6 a bottle. if it comes back, spray it again. a bottle will last you about a year.

its brilliant stuff

yellow218

am I the original poster? This sounds just like me a few years back. Then i found the mould spray that bobbymotors refers too. It's brilliant. would recommend.

Spray the areas as soon as the first spot of mould appears and just let it do its magic. I probably spray it every 2-3 weeks, just little and often and only in the areas I can see mould developing.

Just make sure to open windows when you're doing it/afterwards as it can get a bit overpowering (but then again that might just be me!).

Word of warning- avoid spraying on gloss painted surfaces, over time it does tend to bubble the paint. Doesn't seem to have this effect on my 'vinyl' painted walls though.

Good luck.

martinsurrey

phil24_7 wrote: »

But this will only hide the problem, not solve it!

It will solve it, the problem is that the condensation sits for too long and soaks into the roof plaster, with a UPVC sheeting, not only will it offer an element of insulation, but the water will evaporate much better and faster from the surface of the UPVC than the current plaster (with the inline fan and window circulation).

spadoosh

bobbymotors wrote: »

spray it with hg mould spray, about £6 a bottle. if it comes back, spray it again. a bottle will last you about a year.

its brilliant stuff

Seeing as we're on MSE, i feel compelled to say putting watered down bleach and caustic soda in a spray bottle will give you exactly the same product.

Save yourself £5.95.

phil24_7

Moisture will still sit on the plastic and moult will still likely form. Any moisture getting past this (and it will) will condense and form mould...but you wont be able to see it to sort it. PVC will offer no real insulation either!

The OP knows it is a lack of insulation in this part causing the problems so the way to sort it is to insulate. It is easy enough to carefully cut down some plasterboard, insulate from below using the same insulation as the rest of the roof (maintaining an air gap above the insulation), screw the board back up then fill the joins and paint.

xyz123

Op- do u have or are able to fit decent bathroom extractor fan?