Cold, damp bathroom. What can I do?

[Mrsfrumble]

We moved into a new flat a month ago. The bathroom is north facing and is noticeably colder than the rest of the flat. Although we always open the windows after we've showered and leave the door open to air the room, the air always feels damp and there are patches of black mould appearing on the newly-painted wall and ceiling over the bath

What can I do? I'm annoyed because there is a lively big cupboard in there which I was planning to use for towels and linen but can't because it's so damp and musty smelling. I've thought about a dehumidifier, but there are no plug sockets in the room.

Is there heating in there? Is the window double or single glazed and are there trickle vents? Do you own or rent?

The obvious thing would be to fit an extractor fan, but opening the trickle vents in the window frame will help. Our bathroom is north facing and we couldn't get the windows to open (old house). DP sorted that a few weeks ago and it's made a huge difference. Ventilation and warmth stop this kind of damp and mould.

We rent, so there's only so much we can do. There is a radiator, but it's right next to the door and not facing into the main area of the bathroom (room is kind of an L-shape) so it's not much use. There's an extractor fan but it only runs when the light is switched on, and the windows are double glazed with no trickle vents.

It's obviously a long-standing problem as the hinges for cupboard doors and the on the casing for the blinds are badly rusted. Such a shame as the rest of the flat is perfect for us.

Do you put the heating on though?

Is everything watertight? Is water getting behind the bath/shower?

Can a bigger radiator be fitted or moved?

I would raise it with the landlord as mould is a serious health risk.

One of those freestanding electric towel rails would heat and dry the cold part of the room cheaply. Then you wouldn't get the rise and fall of temperatures that encourage mould.

Like this one.

If there's already an extractor fan it would probably be relatively simply to replace it with a more powerful, modern and quiet one set to run for a period after the light has been switched off. The décor and fixtures are going to deteriorate if the problem persists so it would be worth doing. PigletJohn is good with these things and can probably suggest a specific one.

We have a similar problem in a rented flat, and not even a window. We replaced the knackered old extractor fan - was dead easy as the hole / unit size seems to be standard. We also bought one of those dehumidifier things that are like a sachet of crystals in a plastic tub: the crystals absorbs the water from the air then it trickles into a tub below. It certainly fills up so I think it's working. We do have a huge towel rail / radiator, but it's not cold enough for it to come on yet.

We had black mould on our newly built wet room, well insulated but not a lot of heating, we always opened the window and used the extractor fan we asked a damp expert for ideas. He suggested covering the ceiling with the plasterboard with polystyrene backing. We did this and four winters on not one bit of black mould and definitely warmer. Ask the landlord if he will do this as black mould is dangerous for your health.

A dehumidifier can work - you can get some that can be permanently wired into the bathroom and can run on a thermostat. However your LL may not stump up for that.

This has worked in rental flats I have lived in, in the past: De mould the walls and ceiling using HG or Dettol mould remover - let them dry. Buy a bottle of "anti mould additive" ( can get from Brewers or online, usually not stocked in B&Q) costs about £12 and add to your chosen paint - repaint the room including ceilings. It stops mould coming through for a few years. You can also buy "anti mould paint" in B&Q etc but I have found them to be really thick and hard to apply. Continue to ventilate the room though (open windows etc). Good temporary fix - beats demoulding every week or two - it is not a cure, so the linen cupboard will probably still be unusable sadly.

Anti mould additive
www.brewers.co.uk/product/BN401017V

All very well, but that is treating the symptoms when the landlord can fairly easily deal with the cause.

I would get rid of the mould for a start using this mould spray and raise the issue with your landlord and get it sorted as it could be a serious health risk.