External Ducted Exhaust Fan for Raked Sloped Ceiling

Yes - there are fans where the motor sits above the roof.

https://www.fansonline.com.au/exhaus...aust-fans.html

The whirly bird suggestion is a really bad idea. Whirlybirds don’t move much air - and you shouldn’t exhaust damp air into the ceiling space anyway - especially if you don’t have any ceiling space! It causes condensation which is bad for timber and not good for metal roofs either.

Also, make sure you have air coming into the room or an extraction fan won’t work properly.

Is the best place for the fan at the ceiling apex - or should it be closer to the shower? Get some technical advice.

To kill mould permanently, you need to use diluted vinegar and the ‘three buckets‘ method recommended by Choice. https://www.choice.com.au/home-and-l...g-rid-of-mould

Originally Posted by joynz

Yes - there are fans where the motor sits above the roof.

https://www.fansonline.com.au/exhaus...aust-fans.html

The whirly bird suggestion is a really bad idea. Whirlybirds don’t move much air - and you shouldn’t exhaust damp air into the ceiling space anyway - especially if you don’t have any ceiling space! It causes condensation which is bad for timber and not good for metal roofs either.

Also, make sure you have air coming into the room or an extraction fan won’t work properly.

Is the best place for the fan at the ceiling apex - or should it be closer to the shower? Get some technical advice.

To kill mould permanently, you need to use diluted vinegar and the ‘three buckets‘ method recommended by Choice. https://www.choice.com.au/home-and-l...g-rid-of-mould

Thanks for the reply.

https://www.universalfans.com.au/onl...-roof-fan-150/ I found this one which is a 150mm ducted roof fan, its 328m3/hr whereas I probably only need 200 but they don't really come that small.

How would something like this go secured with a dektite type flashing to the tin roof, are they easy to keep water out of?

The metal tube part is 400mm long though, can I simply cut it? Given the motor is in the cowl externally?

Then can I simply put a vent on the other end of it, and I don't even need flexible ducting so it will just have the vent straight on the underside of it, like this:
https://www.universalfans.com.au/onl...ne-vent-150mm/



The reason I have it suggested for that spot is I plan to move my shower to that position once I eventually renovate that bathroom.

Originally Posted by dammit

Is it possible to install an exhaust fan into a raked sloped ceiling, it only has 150mm void?

Timber (VJ panel) ceiling, and then tin roof on the other side. I don't want it to leak or cause future issues, but wall and window exhausts really aren't feasible in this area.

I think window exhausts look very tacky

I had a suggestion to mount a whirlybird and then discharge an exhaust fan near it, not sure if that is a good suggestion or not.






Any tips on how to kill that mould too and repaint would be greatly appreciated! https://www.bunnings.com.au/flood-75...tment_p0035789 I bought this from Bunnings but it doesn't seem very strong!

you can get side discharge fan heater combo & run flexible duct to the outside wall, the ones I have will fit easily into a roof with 150mm rafters with 38mm roof battens. Mount it centre of the room where you will stand to dry yourself off
inter

What’s the reason that fan location (I.e. above where the OP gets dried?).

I tend to think that’s better than the corner too - but is there any science behind it?

Originally Posted by joynz

What’s the reason that fan location (I.e. above where the OP gets dried?).

I tend to think that’s better than the corner too - but is there any science behind it?

Its just for the heater lamps to get the most benefit out of them, it doesn't matter that much where it's located they usually can't keep up with the steam generation of a really hot shower any way, I've got sloping ceilings in all my bathrooms with centrally located heat lamp fan combos & all the steam is cleared completely from the room in a couple of minutes after the shower is finished, the high end will be the last place to be evacuated, but it's only a matter of 10 - 20 seconds between the low to the highest point.
inter

Good advice on fan positioning and installation here.

https://www.pureventilation.com.au/2...m-exhaust-fan/

I have raked ceilings and a heat lamp wouldn’t be effective as the ceiling is too high.