Bathroom extractor fans

saker75

Hi all.

I have moisture problems in both the en-suite and the main bathroom in my flat. Both are fairly small - and only the en-suite has a window. I get mould in both - I clean it off only for it to appear somewhere else. The doors to these rooms are always open when not in use and I run a dehumidifier in the flat regularly.

I think the two extractor fans are useless but may have too high and unrealistic expectations of what a good one can do. But if anybody has suggestions on dealing with the problem or super amazing fans, please let me know.

S

SternMusik

Don't know about super amazing fans, but the longer the ducting is for the fan the more power it needs to do the job. Thus if the distance from your internal bathroom to the outside wall is four metres then you need a much more powerful fan than if it was two metres.

From my experience, no bathroom fan ever works as well as I would like it to. I had an above the shower light/fan fitting put in recently, with a really powerful fan in the loft, and my mirror still mists up in the bathroom.

Someone told me that in order for the fans to work they should be switched on 5 minutes before taking a shower, so that the air can start moving towards the bathroom fan. I don't have any evidence that it makes a difference though.

TimBuckTeeth

All the standard 4" fans I have seen are fairly useless. They just don't have a high enough flow rate, most will not meet current building control regulations, and they are noisy due to small size needing fast speed, giving a high pitched noise.
You could try a 6" fan, or better getting an inline duct centrifugal fan which is more powerful and quieter. Also stick with decent makes like xpelair and ventaxia for better performance and reliability.
I upgraded from a 100mm to 150mm (XID150) duct fan and it is more powerful, I used a reducing adaptor to allow using 125mm ceiling vent, which is neater but reduces performance slightly.

http://www.dealec.co.uk/acatalog/Xpelair_XID_Inline_Duct_Fans.html
I recommend this range, in 125mm or 150mm size.

There needs to be a big enough gap under the bathroom door or a vent fitted to allow air in, and keep a window open in another room to allow free flow.