Extractor fan under stairs

[notevenadiyer]

Hi

I am thinking of making the space under the stairs into a cloakroom. Happy with all plumbing and stud wall issues but need advice on extractor fan.

I want to put in an extractor, however as a terraced house there is no access to an outside wall. Only way is to go is straight up throught the cupboard in the bathroom directly above then into the loft space. As i am on the ground floor and need to get into the loft i am concerned that moisture ( should be vitrually nil as only a wc and handbasin) might come back down to the fan. I have considered all other options but vertically up seems to be the only way out.

Ay ideas if ok or sugestions?

 

[holmslaw]

..

 

[notevenadiyer]

Thought of that. Previously stated that bathroom is directly above. Not exactlytrue. As an old house and stairs go 90 derees at top the only way to get the pipe up is by cutting a 4" hole throught to the kitchen then go through cupboard directly above in bathroom. wont be able to access external wall by bathroom as an extension has been built with slopped room. This attaches to outer wall of bathroom. no access inside slopped room.
As previously stated i cant see any other way other than going into loft at present.

 

[holmslaw]

..

 

[viewer]

Put the fan in the loft; cable could go up side of pipe.

 

[Taylortwocities]

Make sure your fan is a good powerful one. Most the cheapies wont push air very far (max 3m horizontal)
- sounds like your duct run will be 7-8metres?

 

[stem]

Only way is to go is straight up throught the cupboard in the bathroom directly above then into the loft space.

And then where does it go? If you are venting into the loft space and not to the outside, moisture running back down the fan will be the least of your worries. In the winter, warm moist air blown into your loft will condense on the cold surfaces and could cause all sorts of damp problems & may even rot your roof timbers. This is why lofts have to be ventilated to prevent any warm moist air that seeps up there naturally causing problems.

If you are venting outside via the loft, this won't apply, but you don't say so in your post.

 

[notevenadiyer]

Yes will be about 7 meters. As stated previously not much condensation expected as only cloakroom. I think suggestion of powerful fan a good idea. Any makes recomended. Only want small fan to fit in 4" hole.

 

[ban-all-sheds]

As stated previously not much condensation expected as only cloakroom.

The air will still be a lot warmer than that in the loft, and therefore will naturally contain more moisture.

If you vent it into the loft you will get condensation...

If you have wooden floors why not extract into the floor void.

Thought of that.

Under the ground floor boards?

 

[notevenadiyer]

no good in the middle of the house. Tiled floors. Some solid floors as well

 

[ban-all-sheds]

What's between the proposed room under the stairs and the front and rear walls of the property?

 

[flameport]

no access to an outside wall
...
wont be able to access external wall by bathroom
...
Tiled floors. Some solid floors as well

If you can't find anywhere for an extractor vent other than up to your loft via your kitchen and a bathroom cupboard, where exactly is the waste pipe from the sink and loo going?

 

[pbar]

Don't vent into the loft, it really isn't a great idea. You need to get it outside.
Can you not get at the roof tiles/underlay from inside the loft? If so, you can vent through the tiles, either by changing a tile for a vented one and extracting through that, or by fitting a Lapvent, which you can fit from the inside and causes no disruption to the tiles. Go here to have a look - www.lapvent.co.uk and click on the mechanical extraction link.

 

[notevenadiyer]

thanks flameport for your help. As i am a plumber i think me and a saniflow can take care of that one. I thought i was asking about an extractor fan?

 

[ban-all-sheds]

OK - so you use a saniflo, and therefore a smaller diameter pipe which carries away the minced-up stuff.

But a pipe nonetheless - how's that going to get to the outside?