Bathroom extractor fan install.

[Tinders]

Hi Guys,

I have terrible moisture issues in the downstairs bathroom, there is a extractor fan but its far from the shower area. Its also in the extension, so a flat roof

So im thinking of mounting one closer to the shower in the ceiling, (it will be zone 1 and selv). if i put a fan in the ceiling, it will then have to have a right angle fitting onto a 100/125/150mm dia pipe that will then duct to the outside, ie duct to the side of the extension, this will be a 2m run. Do you think this will work sufficiently to remove moisture?

 

[Jez]

2 threads about extractor fans on the front page.

Zones only extends to 2.25m above floor, so you can do as you wish at ceiling height even above the shower. Your plan should work just fine, screwfix list the flow of each model.

 

[thenewoc]

Personally I'd put it at the top of a wall so you don't need to use ducting pipe and then it is literally only having to move air through the thickness of the wall without any bends.

If you have ceiling space to mount a fan in the void space, I'd recommend the inline manrose ones as they shift about 4 times the amount of air as an axial fan.

 

[Tinders]

Ive only got one outside wall which is 2.5 m away from the shower. The bathroom is a pain to be fair, its freezing in the winter and is always moist. Next year i'll be stripping the roof off and adding insulation, and maybe some in the outside wall.

 

[HardwareGeek]

Depends on the layout of the room - fan should be furthest away from the source of new dry air- then fan will clear the whole room of moist air - dry air should get pulled in under the bathroom door - door should have a big enough gap at the bottom to allow good airflow

Also wouldn't fancy running through a flat roof if it can be avoided

try a good quality quiet humidistat fan then it can run as long as needed to clear the room without being too annoying - a decent fan should have a backdraft shutter to avoid cold breeze coming back into the house or you can fit an external grille with shutters

you can get heat recovery fans aswell if the room is already cold to avoid making it colder

If the duct run gets too long or has bends you might need a centrifugal fan to cope

 

[jpaul]

yes - what's the layout/plan

... so you have a window on that wall ? - that's open a jar when you use the shower, to deliver fresh air.
as said, if you can position the fan high directly through that wall , and it's only 2-3m from shower head then should be fine - that's practically our setup

 

[thenewoc]

Presumably the shower can't be moved to the rear wall so perhaps you could have a boxed in section built along the ceiling on one side to house a decent inline flow fan like a Monrose one. Then route the ducting pipe through the ceiling void if there's room. If the ceiling void isn't deep enough then you'd have to create a boxed in section running the full depth of the room

 

[thenewoc]

Alternatively...

Perhaps you could take ducting pipe back into house, ceiling void of ground floor room behind shower, fit inline flow fan in that ceiling void. Then pass output duct pipe up through floor of room above, make a small boxed in section to cover the duct pipe and within that boxed in area fit a vent which would be facing out over the flat roof.

Would need to check if this could be done within building & fire regs though.