Bathroom extractor fan

[ralphius]

Hello all,

I'm updating a bathroom in a hundred year old end-terrace. I'm adding a shower (the type with a mixer valve off the combi) as it didn't have a shower before and I want to add an inline extractor fan working off the light switch on an overrun timer. I intend to put the extractor fan in the small loft above the bathroom with a short duct to a vent above the shower.

First question, can I legally fit this myself? I consider myself a fairly competent DIY'er (have fitted central heating system myself, except for the gas pipes of course. Have a degree in electronics but am not an electrician or part P certified)

Secondly, what's the recommended way of wiring these? I'm assuming I take a feed off the switched supply to the lights through an isolating switch and to the fan?

Regards,
Ralph

 

[endecotp]

While bathroom electrics may not be allowed for people with "only" degrees in electronics, you're putting the fan in the loft so that doesn't apply.

 

[EFLImpudence]

First question, can I legally fit this myself? I consider myself a fairly competent DIY'er (have fitted central heating system myself, except for the gas pipes of course. Have a degree in electronics but am not an electrician or part P certified)

Any one is legally allowed to do it.
If notifiable work you will have to notify the LA - or employ a registered electrician.

As you will be making an "addition or alteration" to a circuit, if it is in the zones of the location it is notifiable.
If the ceiling is more than 2.25m from the floor, it is not in a zone, and so, not.

Secondly, what's the recommended way of wiring these? I'm assuming I take a feed off the switched supply to the lights through an isolating switch and to the fan?

You will require a line, switched line, neutral and earth so probably wiring at the light will be needed.
There may be a neutral at the switch.

An isolating three-pole switch will be a good idea but not a requirement.

 

[ban-all-sheds]

I want to add an inline extractor fan working off the light switch on an overrun timer.

Does the bathroom have a window?

Just wondering if a fan which comes on whenever the light is turned on, no matter what the use of the room is, and/or if having to have the light on when the shower is used in daylight, is the best idea.

 

[JohnD]

can you see a downside?

 

[ericmark]

Does the bathroom have a window?

Just wondering if a fan which comes on whenever the light is turned on, no matter what the use of the room is, and/or if having to have the light on when the shower is used in daylight, is the best idea.

I seem to remember it comes under Part F and if the window will open then fan is not required so you can do what you like, but if window does not open then it is a requirement that you can switch on the fan without the lights.

 

[ban-all-sheds]

can you see a downside?

Other than a fan running when not needed and/or a light on when not needed, no.

 

[JohnD]

Just personal preference, then.

 

[ralphius]

Thanks for the replies, based on your comments I've decided to do the job myself as the ceiling is at just over 2.4m from the floor. EFLImpudence that's exactly what I needed to know


In answer to other questions,

Does the bathroom have a window?

Yes the bathroom has a small opening frosted glass window, facing directly north at my neighbours property. I usually use the light.

 

[ban-all-sheds]

Do you want the fan to come on whenever you turn the light on?

 

[endecotp]

as the ceiling is at just over 2.4m from the floor. EFLImpudence that's exactly what I needed to know

You say you're fitting an inlne extractor fan in the loft - the ceiling height is irrelevant.

 

[EFLImpudence]

No, it isn't.

If the ceiling were less than 2.25m, it would be within the zones and "any addition or alteration to existing circuits in a special location" were carried out by adding the fan wiring to it, then it would be notifiable.

The ceiling is higher in this case so it does not matter either way, but -
were it lower, are you saying that the lighting circuit is not an "existing circuit in a special location"?

http://www.legislation.gov.uk/uksi/2012/3119/regulation/6/made

 

[JohnD]

"within a room"

If the fan is not in the bathroom, but in the loft above, it cannot be in zones.

 

[EFLImpudence]

Is "within a room" not where the lighting circuit is?

 

[JohnD]

the ceiling rose probably is. Downlighters, no. Cables, no.

If I cared enough, I could do all the wiring in the loft, but I don't think I've seen a bathroom ceiling so low that the position of the rose is a concern.