Bathroom Fan Recommendation

[imroberts]

I've recently moved house and currently have no bathroom fan. I'm looking to fit one before the winter comes and the windows aren't open all the time.

Two important factors to me are
1) the fan is effective, and can either keep up with the steam generated by a shower or clear it within, say, 5 minutes afterwards
2) it should be as quiet as possible, the bathroom is right next to the main bedroom and I'm easily disturbed

Firstly, am I right in thinking a ceiling mounted fan would be more effective than a wall mounted fan? The loft space is easily accessible and the bathroom is along the gable end so fitting and venting either won't be a problem.

Secondly, what kind of fan should I be looking at? I understand in-line fans tend to be quieter, though given the position of the bathroom I shouldn't need more than 2-3 feet of ducting anyway, so would an in-line model actually be that much different? I assume installing more ducting just to get the fan further away and hence quieter, will make it less effective?

Can anyone recommend any particularly effective, quiet, reliable models?

 

[blup]

I use one of the Axxia inline ceiling mounted silent models, it clears most of the steam with a timed ten minute overrun. It runs from the light switch with a separate isolator for the times of the day or night when the fan is not needed.

I would probably have gone for a more powerful wall mounted fan if circumstances had allowed

Obviously every situation differs.

Blup

 

[ericmark]

The in-line fan I fitted in mothers wetroom sounded like an electric drill being used, re-mounted with sponge above and below mounting screws and could not hear it running, think today I would be looking at a heat recovery unit rather than simple fan, but main point is noise is all about how it is mounted.

 

[ericmark]

The in-line fan I fitted in mothers wetroom sounded like an electric drill being used, re-mounted with sponge above and below mounting screws and could not hear it running, think today I would be looking at a heat recovery unit rather than simple fan, but main point is noise is all about how it is mounted.

 

[JohnD]

I had an early version of a heat recovery fan by Dimplex, it sucked out the warm air from the kitchen and transferred the heat to an equal amount of fresh air from inside. What I hadn't previously taken into account is that the traditional extractor creates a modest amount of suction, which prevents steam and odours diffusing into the house, as it draws air into the room through gaps and prevents it escaping out.

So although I might get one for ventilation, and it can catch incoming pollen and dust, I don't think think they're suitable for a kitchen or bathroom. Mine was extremely quiet.

(in the kitchen, the filter also needed frequent cleaning from greasy cooking vapours)

 

[JohnD]

Firstly, am I right in thinking a ceiling mounted fan would be more effective than a wall mounted fan? The loft space is easily accessible and the bathroom is along the gable end so fitting and venting either won't be a problem.

Yes. Water vapour is lighter than air (hence clouds) so it will rise towards the ceiling.

Typical 100mm wall fans extract around 80 cu.m/hr, which is just about enough for a bathroom or WC provided you run them all the time the room is in use, with a timed overrun. But showers can be very steamy, so more powerful is better.

But you can get a ducted inline fan with two or three times the power, which is also quieter, especially if you mount it on a board isolated from the joists with foam underlay or something.

The Soler & Palau have a good reputation, and seem well made.

https://www.tlc-direct.co.uk/Products/SLTD160T.html
https://www.tlc-direct.co.uk/Products/SLTD250.html
https://www.tlc-direct.co.uk/Products/SLTD350.html

This type usually has a ball-bearing motor which is likely to have a long, quiet life (old wall fans often don't, and don't). Look at the db numbers to choose a quiet one, and the air throughput numbers. You will easily spot the good ones. You might consider a two-speed fan and see if the lower speed is adequate.

Cheap ones (in every sense) are also available.

A good installation method is to wire them so they come on with the light switch, and autiomatically continue on the timer. There are a few (usually older) people who have an aversion to ventilation and think that all fans are noisy and expensive to run. The cost of electricity for a typical modern fan is in the region of 15 pence per 100 operating hours. The most powerful one I show is 30 hours for 15 pence at full power.

 

[ericmark]

Yes. Water vapour is lighter than air (hence clouds) so it will rise towards the ceiling.

This will be why dew forms at ground level? Because water vapour is opaque it is warmed by the suns rays so is warmer than the surrounding air, so it raises, but water vapour is in the main heavier than air, in the wet room which had a heated floor it really did not matter, if water landed on the floor it would soon evaporate, but most bathrooms don't have a heated floor, so any carpet will get damp, which will take time to dry, so a fan needs to run far longer than the 15 minutes it says in building regulations if there is a carpet, putting a towel down on a tiled floor, then removing the towel to wash it, means the room dries a lot faster, same applies if towel put on towel rail, the towel is dried faster so fan needs to run for less time.

The problem is time to dry bathroom after a shower is far longer than time required to remove smells, and to conserve energy we don't want the fan running longer than required, I take your point about heat recovery units, very good if you have an open flue fire, they ensure flue gases are not sucked into the house, but the type where the pipe through the wall is the heat exchanger, often they only blow out, and it is the suction in the room that draws the air in, so unless doors are closed it becomes an extractor rather than heat recovery unit.

 

[Taylortwocities]

Use a fan size calculator to find out what performance fan you need!
Here’s one https://www.tlc-direct.co.uk/Technical/Ventilation/Ventilation4.html

Keep duct runs short

Don’t buy cheap. Low cost fans have performance to match.

Make sure enough air can get in to the room, or you’ll be creating a suction.

 

[JohnD]

t water vapour is in the main heavier than air

nope.

https://en.wikipedia.org/wiki/Water_vapor#At_equal_temperatures

 

[ericmark]

nope.

https://en.wikipedia.org/wiki/Water_vapor#At_equal_temperatures

Would that not depend on % humidity of the air? i.e. how much water vapour is in the air, I remember driving pass a power station with warning about ice on the road as the steam and resulting water vapour could end up causing black ice on the road. Saturated air i.e. 100% humidity does not work the same as mixing 50% with 75% air.

 

[JohnD]

I think the ice and dew will be because the ground is cold; possibly colder than the air.

But water vapour is certainly lighter than air.

 

[EFLImpudence]

This will be why dew forms at ground level?

More likely is the fact that dew is the name given to condensation which forms on the ground.

Because water vapour is opaque

There is confusion in the definition of water vapour.

Some sites give the name to the invisible gas, for example, just at the spout exit of a kettle and some give the name to the white cloud above that which is condensed suspended water droplets (clouds) which form above the invisible gas because of the lower temperature of the air there.

It presumably rises because the air in which it is suspended is warmer than the general air in the room.
If the droplets became too large to be suspended then it would rain.


How effective a fan will be also depends on the humidity of the replacement air being drawn in.
Some houses are very humid (many plants, washing 'drying', animals, too many people) and feel like the tropical house at a zoo when one enters. Were this the case then the fan might even make the bathroom worse and a fan in the very humid part of the house drawing the air the other way might be more useful.

 

[ericmark]

Definition of water vapour I would say it has to me mixture of air and water, steam (over 100°C) is not water, and it is clear, as it changes state then it becomes water, but this should not happen in a bathroom, and over 100% humidity also no longer water vapour, it is precipitation be it rain, snow or hail.

Years ago we has a pane of glass to remove water from bathroom, there was a tray formed below the glass and holes to drain water to outside, but today they fit two panes with a space between and no drain to outside, so water condenses on every cold pipe.

 

[EFLImpudence]

Definition of water vapour I would say it has to me mixture of air and water,

Water vapour is water vapour whether in air or not; the same as oxygen.

steam (over 100°C) is not water, and it is clear,

Invisible, yes. That was always my view but as I said, some sites call this state water vapour and the visible cloud, steam.
I no longer know which is correct and in similar discussion before JohnW2 and I were taught opposite views.

as it changes state then it becomes water, but this should not happen in a bathroom,

Obviously it will not rain in the bathroom as it will condense on surfaces.

and over 100% humidity also no longer water vapour, it is precipitation be it rain, snow or hail.

Outside, yes.

Years ago we has a pane of glass to remove water from bathroom,

Not sure that was the reason for the glass.

there was a tray formed below the glass and holes to drain water to outside, but today they fit two panes with a space between and no drain to outside,

I think they still have drain holes somewhere.

so water condenses on every cold pipe.

Water will condense on cold pipes and other cold parts whatever the arrangement. - that's physics.

 

[Braddy07]

I just had a whole new bathroom installed, got a Manrose 100T inline fan fitted, got a grill in the ceiling with a short run of ducting to the fan which is mounted in the loft on a plank then fixed to the joists and then ducted out via another short run to outside vent.
It's on a overrun timer for a few mins and manages to clear the steam quite well.
It's got 3 speeds which I run on the fastest and i don't find it loud at all, just like a low hum from the air moving through the ducting.

So far I'm really happy with it and think you can pick it up from the net for less than £50