Overhead bathroom extractor and duct

BUDFORCE

BUDFORCE

BUDFORCE

Soldato
Joined
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Hi guys,

I have what I believe it called an in-line bathroom extractor over the shower.

EDIT: Fan is mounted in the ceiling.

So, the extractor fan has a 4" backing pipe which is screwed onto the plaster board above the shower, that is wired to the mains, which then goes to a switch on the wall. The existing one is a "Silavent SDF 100T" and runs from 240v

That goes through the plaster board ceiling into the loft, which then air duct is jubilee clipped to that, and the other end is jubilee clipped to a roof vent. The air duct is 4" gauge.

The fan is playing up, plus whoever did the job the first time (I suspect the builders and the house is only circa 20 years old) did a real crappy job, using 2 different peices of vent duct, gaffer taped in the middle etc, I am wanting to replace the extractor fan and all of the ducting. It looks easy enough to do the access in the loft is fine etc.

Forgive my noobness, but searching on ebay for "air duct" doesnt find the right stuff, its like plastic 4" stuff, do you know what the proper name is?

Also, any recommendations on a replacement fan, a direct replacement is around £15, but I dont mind spending more to get a good one. I am not complete against buying a larger one either, the shower is in a small room and really get condensed up and the paint doesnt last because of it, i am after maximum extraction :)

....within reason.
 
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OK, I can see the inline ones do shift a hell of a lot more air.

I am guessing then, you need two pieces of ducting, one each side of the fan, one end out the top of the roof, the other end down to a vent?

I would be replacing the existing ceiling mounted fan, so I would guess I would need a replacement internal vent?

So vent on ceiling of shower screwed in plaster board > duct > in-line fan > duct > external vent.

In which case, I would also need an internal vent above the shower to replace where the existing fan is.

That right?

EDIT:

Thoughts on this? The roof external vent is 4" that part cannot be changed, could you run a 6" fan and duct and use an adapter to drop it to 4" just before the external vent?

The 6" version inlines do double extraction of the 4", and making a bigger hole in the plaster board above the shower isnt an issue.
 
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Yes that’s correct, you would need an internal facia piece to replace the existing fan, one came in the entry level kit that linked. Ducting goes either side of the fan as you have written.

You can get a 6” version and adapt it down before it exits the roof, that isn’t a problem. The less 4” pipe you have on the the less restrictive adapting down will be.

As I mentioned the main advantage is that they shift more air for the noise produced. I went with a 4” model that shifts about the same amount of air but you can hardly hear it when it’s on. They also look a lot better IMO.
 
Ok thanks guys.

I stuck to 4" in the end, finding a decent ceiling grille cover was the hardest part!

Went for the Manrose MF100T in the end.
 
BUDFORCE said:
Ok thanks guys.

I stuck to 4" in the end, finding a decent ceiling grille cover was the hardest part!

Went for the Manrose MF100T in the end.
Click to expand...

Make sure it has a seal that drops into place when turned off. As in my original fans didn't and basically caused a draught and all the hot air to be taken out the room increasing energy bills long term.

Now I have fans which close the vent when not on so no heat can escape.
 
Job done.

It's louder then imagined, the fan itself isnt the real noise but the noise of the air going through the intake vent above the shower, I guess you know its working though.

Anoyingly I bought 4" jubilee clips thinking 4" duct......... of course, they dont fit...... I managed to reuse some of the old ones and cable tied/taped one of the connections, so ill sort that out when I get some more, 5 inch this time :)

Pretty pleased though, does clear out the moisture a lot better than the old one, which was on its way out anyway.
 
It is recommended to insulate the ducting in the attic with either that foil bubblewrap or rockwool/glass (helps stop condensation inside the ducting):)
Also if you are using an in line fan to mount it higher than the ducting so any conensation does not pool into the inline fan :)
 
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