Extractor fan for non window bathroom

[Lukman]

Hi.  I am after some advice on a bathroom fan for a bathroom without a window.  This is in a flat and the existing bathroom fan is connected to ducting, which is approximately 8 metres before it is vented outside.  The bathroom is 2.5m (l) x 2 m (w) x 2.3 (h) = 11.5m3.  The fan that's in at the moment does nothing and I have mould.  I have looked at the Cyclone 7 fan from Envirovent.  It is very expensive and wanted to see if anyone here has used this before and some feedback that would help me with my problem.  

Thanks

Lukman

 

[Gian]

Hi.  I am after some advice on a bathroom fan for a bathroom without a window.  This is in a flat and the existing bathroom fan is connected to ducting, which is approximately 8 metres before it is vented outside.  The bathroom is 2.5m (l) x 2 m (w) x 2.3 (h) = 11.5m3.  The fan that's in at the moment does nothing and I have mould.  I have looked at the Cyclone 7 fan from Envirovent.  It is very expensive and wanted to see if anyone here has used this before and some feedback that would help me with my problem.  

Thanks

Lukman

Only advise I have is don't buy cheap, by quality and make sure its capable of dealing with the 8 meter distance. I have done the budget fans and never again. 

 

[Bruspark]

8 m is a very long distance.  Things that will help are :

Use a powerful 'mixed flow' inline fan in the ceiling /loft that is roughly 1/3 of the way along the 8 m
Use a decent fan !!    I've had good results with these over 6m distances  https://www.screwfix.com/p/vent-axia-acm100t-21w-in-line-bathroom-extractor-fan/53730
Use rigid 100mm ventilation pipe at every opportunity, avoid unnecessary bends and use the bendy wrinky stuff only where unavoidable.
Make sure there is a good source of replacement air coming into the bathroom (e.g. 10mm gap right across under the door) or the fan has to fight a vacuum forming in the bathroom as wellas the length of vent . .

 

[SPECIAL LOCATION]

Most axial fans can't shift more than the width of a wall...

anything 2m or more in length probably needs a centrifugal fan...

But as Bruspark said.. 

If you want to extract air from a space..

There MUST be the ability to allow the same rate of air to enter that space...

Otherwise you will never get any airflow...

and without airflow any environment with moisture or steam will have mould problems..

[ Try an experiment yourself..

Blow down a 0.5m length of hosepipe, compared to an 8m length of hosepipe...

You will then get an idea how much harder work it is to shift air a longer distance! ]

Guinness    

 

[Murdoch]

OP - have you checked you have sufficient airflow under the bathroom door for your existing fan?

As others say, buying cheap won't actually achieve anything.

 

[Gian]

OP - have you checked you have sufficient airflow under the bathroom door for your existing fan?

As others say, buying cheap won't actually achieve anything.

I take it its a flat, I actually had bad issues with this like you. A bothroom concealed not many options. For me a quality fan but check it will achieve your 8 meters. And as others have said air flow is needed. I rented a place so it was difficult to justifie cost. What I did was install in my flat with consent of the land lord was a humidifier. It was a large unit that did the job for us. We were lucky as we had a airvent put in close to the bathroom as well. It helped. I also at the time cleaned and painted with zizners. Difficult situation 

 

[Lukman]

Hello 

Many thanks for the responses.  Really appreciate your feedback.  I have come accross this as an alternative to the Cyclone 7 from Envirovent.  It is much cheaper and offers a 5 year warranty.  It is a mixed flow fan and wanted to ask if anyone has used this.  Greenwood Omnique OF100GIP 

Thanks

 

[Bruspark]

I haven't used it -as already mentioned pushing air through 8m of ducting with bends from one end is a big challenge.  Hence my suggestion of an inline mixed flow fan .   
 

I looked at the Greenwood’s installation data which is short on performance data also repeats my suggestion to use rigid vent pipe 

 

[binky]

8 m is a very long distance.  Things that will help are :

Use a powerful 'mixed flow' inline fan in the ceiling /loft that is roughly 1/3 of the way along the 8 m
Use a decent fan !!    I've had good results with these over 6m distances  https://www.screwfix.com/p/vent-axia-acm100t-21w-in-line-bathroom-extractor-fan/53730
Use rigid 100mm ventilation pipe at every opportunity, avoid unnecessary bends and use the bendy wrinky stuff only where unavoidable.
Make sure there is a good source of replacement air coming into the bathroom (e.g. 10mm gap right across under the door) or the fan has to fight a vacuum forming in the bathroom as wellas the length of vent . .

I have a very similar fan in my bathroom, works a treat! 

 

[Sidney]

I have a very similar fan in my bathroom, works a treat! 

Funnily enough, so have I and it does work well.

Back to the OP, I've found a little bit of housekeeping after a shower often helps, squeegee down the walls or use something like a Karcher window vac to remove excess moisture that accumulates on walls. I live in a mid-terraced house and damp is a bit of a problem, even down to educating my kids to shut the door during and after a shower to slow the humidity spreading through the property, but also good airflow under the bathroom door is essential.

Some days I even have to vac the windows when the temperature drops outside, the trick is to try and keep the humidity down as much as possible, all that condensation on the walls after a bath or shower has to go somewhere.

 

[binky]

Some days I even have to vac the windows when the temperature drops outside, the trick is to try and keep the humidity down as much as possible, all that condensation on the walls after a bath or shower has to go somewhere.

I know exctly what you are on about. My house is 1886 mid terrace single skin brick construction. Damp has a habit of moving around the property unless dealt with at source, hence the oversized fan in the bathroom. I also use woodburners, they suck air through the property and keep it all moving. These houses were never designed to be sealed up with double glazing and PVC doors.

 

[Murdoch]

I know exctly what you are on about. My house is 1886 mid terrace single skin brick construction. Damp has a habit of moving around the property unless dealt with at source, hence the oversized fan in the bathroom. I also use woodburners, they suck air through the property and keep it all moving. These houses were never designed to be sealed up with double glazing and PVC doors.

No houses are really designed to be sealed up unless they have proper air circulation systems in them.

But try telling tenants not to dry clothes indoors with the windows shut ............ when they are complaining about mould and damp!

 

[ProDave]

But try telling tenants not to dry clothes indoors with the windows shut ............ when they are complaining about mould and damp!

I did a batch or rental EICR's this week and all of them had the fan isolators turned off.  (my own rental does not have such a silly switch)

 

[Sidney]

I did a batch or rental EICR's this week and all of them had the fan isolators turned off.  (my own rental does not have such a silly switch)

That's why I try to fit them out of reach, ideally in the loft near the fan.

 

[binky]

But try telling tenants not to dry clothes indoors with the windows shut ............ when they are complaining about mould and damp!

seen that so many times. People really are dumb these days. 

 

[Murdoch]

seen that so many times. People really are dumb these days. 

yes

i have had tenants tell me that ventilation doesn’t help. 

 

[benvictor]

But try telling tenants not to dry clothes indoors with the windows shut ............ when they are complaining about mould and damp!

Haha a timeless problem!