Extractor fan location in bathroom

What is the best location for the extractor fan according to regs ?
Can it be fitted above the shower ?

You can fit a fan above a shower.

so long as the extractor fan is suitably rated then yes it can go above the shower

Guys, you should point out that the ONLY fan that can now go directly above a shower, or in a shower cubicle must not be rated at more that 12V SELV and be powered by an isolating transformer.

Is there a min distance between the shower head and extractor fan ?

Also does the transformer and isolation switch fitted ouside the bathroom ?

Do those regulations also apply if the fan is actually located half-way along the run of ducting to the outside wall and all connections are above the ceiling?

Panjandrum said:

Do those regulations also apply if the fan is actually located half-way along the run of ducting to the outside wall and all connections are above the ceiling?

Click to expand...

If the fan is the inline type, and is located more than 500mm from the intake grill, and all eletrical connections are remote from the bathroom, then Yes it can be a 220V fan. Note, that if the fan is operated by the light switch or by a similar independant switch, this is OK so long as the switch complies with the regulations.

Thanks FWL - and apologies Hdiy if I am hijacking your thread.
I would really like the switched live for my fan to come from the pump's switched live (its not an electric shower). Fan on lighting circuit. Pump on fused spur off ring.
I can find the right connection on the pump, but am not clear on what's involved in taking that as feed to the fan?

run three and earth from the pump (which the switched live comes from) vai a fan isolator to the fan.

btw the sense inputs on fans draw extremely low current so you don't have to worry about overloading stuff with it.

Panjandrum said:

Thanks FWL -

I would really like the switched live for my fan to come from the pump's switched live (its not an electric shower). Fan on lighting circuit. Pump on fused spur off ring.
I can find the right connection on the pump, but am not clear on what's involved in taking that as feed to the fan?

Click to expand...

Glad to Help.

Regarding feeding the fan from the pump, this is possible.

If the fan incorporates a timer or humidistat

You would need to run a Three Core and Earth cable from the FCU on the pump feed to the fan, Via a three pole fan Isolator. You will need to decide which core to use as the Permanent Live and which to use as the switched live, but the BLUE is always the Neutral.

Connect the PERMANENT live to the Supply side of the FCU (THIS MUST BE SEPERATELY FUSED DOWN TO 3A VIA AN UNSWITCHED FCU AS IT WILL BE FED DIRECTLY FROM THE RING MAIN OTHERWISE).

Connect the Switched Live to the OUTPUT terminal of the FCU (The one feeding the pump live).

Connect the BLUE (NEUTRAL) to the SUPPLY side of the FCU, and then Feed the Fan VIA the unswitched FCU neutral terminals in the normal way.

Then all three cores must go through a triple pole Isolator before being terminated in the fan. This will have the termianls marked for the correct operation of the fan.


If the Fan has no Timer or Humidistat

Simply connect a Twin and Earth Cable to the OUTPUT side of the FCU for the Pump, then connect this to the fan. This DOES NOT require a seperate Isolator as it does not have a permanent feed to it, and by removing the fuse, it would be safe to carry out maintenance on the Fan.


As a side not to this, the incorporation of the timer circuit is necessary in a bathroom where the fan over-running will significantly reduce the build up of steam, moisture and eventually damp. If the fan you have does not have such a device, then I would give this serious consideration. It may make wiring the fan in more complicated, but it will reduce damp no end.

Best location is furthest point from the rooms natural ventilaion source. Also consider type of fan to use. Up to 2mts ducting a standard one should be fine above three mts look to use a centrifugal type