Installing Ceiling Vent in Bathroom

[nickldn]

I need some advice about increasing bathroom ventilation.

I've got a bit of a mould problem in the bathroom, caused by lack of ventilation. Patches of mould are appearing on the ceiling around the edges of the bathroom. Generally, the bathroom is not mouldy, so it's not a big issue, looks unsightly though.

I leave the window open after showers, etc. but looks like that's not enough to get rid of the moisture quickly. I've been up in the loft and the eves are not blocked by loft insulation, so air can escape freely. I can't see any evidence of a condensation problem in the loft, which is good news.

I want to avoid having to fit an electric fan in the bathroom, instead I was hoping to get away with was a ceiling vent linked to existing roof ventilation.

I think the bathroom wall in my house was moved at some point, because there appears to be a roof vent with a little chimney, which has a piece of plastic ducting that seems to go from the roof into the stud wall between the bathroom and the bedroom. I am thinking that vent was originally for the bathroom, because it doesn't seem to do anything else at the moment, but I could be totally mistaken.

Ideally I'd like to make a smallish hole in the bathroom ceiling and put in a vent, which I could link up with the ducting from the roof vent.

Does anyone know if this is a good idea to move the current ducting which goes into the wall, and if a ceiling vent, without an electric fan is it likely to provide enough ventilation for the bathroom?

Any help would be greatly appreciated.

Nick

 

[Burnerman]

You're not confusing this 'little chimney' with the soil vent pipe, are you....?
Time to consider an electric fan with a short duct to take the moisture outside if at all possible - naturally it mustn't vent into the loft space.
John

 

[nickldn]

Thank you for your reply John.....I think it may well be a soil vent pipe....better not touch that then.

I can't really go through the wall, it's going to have to be a ceiling fan with ducting into the loft. What's the best way to create an external duct from the loft space without having to make another hole in the roof? Is it possible to duct out through one of the eves, or any other way?

 

[^woody^]

I doubt a vent on its own would help, and with a roof terminal you need to ensure that you don't get back draught into the bathroom

You should also try and insulate above the ceiling where the mould is, as it may just be a case of a cold ceiling. But keep some air gap at the eaves

 

[Burnerman]

Its perfectly possible to go through the bathroom ceiling, into the loft space and then down and out through the soffits, of you have room....you can use flexible ducting for this, but its best to have a gentle fall to outside so no pockets of moisture can be trapped.
John

 

[nickldn]

I'll definitely try out the cold ceiling theory, I've just been up into the loft and put in another layer of spare insulation around the edge of the bathroom. We'll see what effect that has...hopefully it'll lessen the mould a bit.

If not I'll try a fan ducted through the soffits, sounds better than doing anything with the roof.

Thank you for all your advice, it's much appreciated.