Bathroom extractor fan vent height

Joined
2 Apr 2008
Messages
200
Reaction score
1
Location
Hampshire
Country
United Kingdom
Hi folks,

I'm doing a bit of gentle improvement on my bathroom, and I'd like to add an extractor fan. Because of the layout of the room it would be far far easier if I could fit the "inlet" vent for the extractor about 18" above the floor - either in the bath side panel or in the box next to it which has the shower controls and plumbing mounted in it. Outlet pipe would then go along under the bath and out the wall near the drain.

Mounting in the ceiling is impossible because there's no access to the space above (flat roof). There is no outside wall area available - it's all either window, bath or sink. Only other option is to go through another room - and that's so much hassle that if that's the only option, I just won't do it.

In terms of electrical safety, I'd either have an in-line fan so that the electrical part would not be subject to getting wet, or mount it away from the taps/drain end, or both.

My question is whether extractor vents work properly at low heights. I've found all sorts of information about mounting them near the source of steam, far from the source of fresh air, not too close to the ceiling etc. - but not been able to find anything at all about mounting them low down.

We're trying to promote air flow, right, not suck out steam - so it's not about "steam rises". Are they all high up because it's normally convenient to do it that way (not in this case) or is there a reason?

Thanks!
-Mark
 
Sponsored Links
Generally, the recomendation is 1800 from the floor and 300 from a room corner. Also in the opposite corner of the room to the door

It will not work effectively at a low level as an extract fan, but may promote air flow. Then there is a possible safety issue as the fan is more at risk of being touched, or [little] fingers being proded into it

You want a 10mm gap below the bathoom door so that air is drawn into the bathroom, across, and out the extract fan

It is possible to fit the fan to the ceiling and vent through the roof. You'll need the correct terminal etc, but its possible and best.

The other option is a window fan.

Or this may work - mount the fan at high level and if possible duct the fan down to an outlet under the bath. This may require some unsightly boxing in though
 
It is possible to fit the fan to the ceiling and vent through the roof. You'll need the correct terminal etc, but its possible and best.

The other option is a window fan.

do what he says!

if you insist on an inline fan be very careful.if the duct run/number of bends is exceeded,the fan can stall.this then creates a fire hazard you cant see.
 
Sponsored Links
Hi,

Thanks for the replies - very useful.

There's no problem hiding the piping - the problem is I want this to be a reasonably small job, rather than one involving dismantling the (non-dismatleable) fixtures in the room and taking the roof off.

I've got a clearer idea of what I need to do now, thanks. Seems I'm going to have to opt for a surface-mount fan, rather than in-line, because none of the inline ones have humidistats. (I presume because the humid air wouldn't get down the pipe to the sensor unless the fan was running...) And it seems I may have to bite the bullet and hack stuff apart...

Cheers,
Mark
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top