Which bathroom extractor fan features?

[Sprogginz]

I already have a vent above the bath that seems to be the correct size for an electric extractor fan but need to check.

I'm looking at extractors on websites such as Screwfix but I've realised I don't know which one I should get because it seems there are some features that I may not realise are available and could be important to me.

I've seen one from £10 which have actually got decent reviews but I don't think they have built-in timers. I 'think' a timer is important unless anyone sees it as a possible disadvantage?

A lot of them say 'no built-in shutter', is it important or worth paying extra to get one that does?

Apart from maybe paying extra to get a quiet one, are there different features for turning on the extractor itself? I'm wondering if they have features where you can pull the cord to switch on the light but not activate the extractor such as for when you get up in the middle of the night to take a pee? Is there an override feature so that you can cancel the timer?

If you can let me know what I should know or take into consideration then I'd be very grateful including any actual product recommendations.

Thanks very much and Happy New Year!

 

[Taylortwocities]

First things first:

• The vent above the bath: does it go anywhere? Is there a duct attached that goes outside? If it does go outside, is there a flap on the end to stop air going back in?
• The room: What are the dimensions? The fan size depends on the room size. Is there an opening window?
• Fan switch on and off: There's lots of options. You could have a separate switch just for the fan, or a disable switch (I dont like these because they are always off). Dont bother with a humidistat control, they never work properly.

Give us some more info and can help more.

PS There are some budget fans out there but you generally get what you pay for. I have seen £15 fans that can barely push air through a 9" length of pipe.

 

[Sprogginz]

Thanks very much for your help, really appreciate it.

Hopefully the photos will help.

• Looks like there's no duct inside the hole. On the outside it's a clay airbrick so no flaps.
• The dimensions are (w)1.96m x (l)1.7m x (h)2.3m. There is a double glazed window that can open.

During the summer it's not a problem because we can simply open the window. We could leave the door open but that seems to set off the smoke alarm nowadays and the landing is fairly cold as well. I'm just wondering, let's say I can get an effective extractor, would that suck out the warmth anyway? So far, despite the walls being so wet after use, the Zinsser wall paint seems to be doing a pretty good job so far after 5 years.



Thanks again.

 

[endecotp]

I like having a double switch on the wall, so you can turn on the light without the fan and vice-versa. But if you don’t currently have that, it may involve burying additional cables in the wall which could be a lot of work. So what wiring is currently in place?

You should probably fit a short bit of plastic duct between the back of the fan air brick, so that the dampness is kept out of the brickwork.

 

[JohnD]

Do you have steamy showers?

If so, you need a above-average fan.

If not, you may get by with a small 100mm

The minimum to look for is an extract rate of 80 cubic metres per hour, and a noise of 25 dba or less.

Better fans have ball-bearing motors.

Cheap fans are not as good and do not last long. They get quite noisy with wear and people stop using them.

As you have no external vent cover you will need one with its own backdraught shutter.

The Envirovent SIL100T is very good and good value.
https://www.electricals247.co.uk/en...MI_OiDp7yh7QIV1e3tCh00dwfYEAQYASABEgJnMPD_BwE

If you have room for a 150mm (6-inch) fan you can get more power, which you will need if you have steamy showers

I strongly favour a fan that comes on automatically with the light switch. Otherwise people will not bother turning it on. Electricity cost is negligible.

A fan that is quiet, as above, will not irritate people so they feel impelled not to use it.

If it is quiet, there is no reason not to use it.

 

[Taylortwocities]

My fan calculator says you need 38.3 litres per second, so an above average fan.

Major consideration/concern is the position. Nobody has mentioned this. Your airbrick hole is within the shower area, and with a ceiling beight of 2.3 metres, that puts (at least some of) the fan within Zone 1. This means that you cannot have a mains powered fan there. You'll need a 12v fan to be compliant with the regs. Do you have access to the roof space above the bathroom?

Re the hole. Easiest way is the install a short length of pipe from the inside so the end is flush with the airbrick outside. To do it properly, you should fit ventilation cowl with flaps on the outside. Make sure the pipe slants slightly from inside to outside so that any water doesnt run into the room. There will be a lot os space around the pipe, that horrible expanding foam stuff is handy here.

If you are going minimum spec then one of these will manage https://www.tlc-direct.co.uk/Products/XPLV100T.html
If you want to do it properly one of these fabulous fans https://www.tlc-direct.co.uk/Products/ADICON30ECOLV.html
plus a timer module https://www.tlc-direct.co.uk/Products/ADPCTSLV.html

Both have backdraft flaps.
No here near your budget £10 fan!
Wire the fan as a timer fan including a fan isolator switch so you can turn them off if you want to.

The point of the fan is to pull condensation out of the room. You will get mould eventually. yes, you'll lose a bit of heat too, but thats the price you pay.

 

[Sprogginz]

The Envirovent SIL100T is very good and good value.
https://www.electricals247.co.uk/en...MI_OiDp7yh7QIV1e3tCh00dwfYEAQYASABEgJnMPD_BwE

Wow, that one seems too good to be true! Not much more money yet extracts more but quieter and uses less electricity! What's going on?
Thanks very much, I'll try to see if I can fit a 150mm one instead or expand the hole somehow if need be. Seems like it'll be worth it.

 

[Sprogginz]

...that puts (at least some of) the fan within Zone 1. This means that you cannot have a mains powered fan there. You'll need a 12v fan to be compliant with the regs. Do you have access to the roof space above the bathroom?

Oh bum, replied too soon! Yes, it's coming back to me now when I first looked into this a while ago, Zone 1 = 12v!
I do have access to the roof space above, trying to remember now if there was a further issue that caused me stop other than laziness.
Thank you very much again, I'll digest this all again along with your other advice, really need to get this sorted.

 

[Taylortwocities]

You'll need access to the loft to more easily get to the lighting circuit for the connections. The 12v transformer can go anywhere handy.

 

[EFLImpudence]

Major consideration/concern is the position. Nobody has mentioned this. Your airbrick hole is within the shower area, and with a ceiling beight of 2.3 metres, that puts (at least some of) the fan within Zone 1. This means that you cannot have a mains powered fan there. You'll need a 12v fan to be compliant with the regs.

Maybe no one has mentioned it is because it is not true - as long as manufacturer states it is suitable for zone 1.

 

[JohnD]

Sometimes you can put a mains fan in zone 1, but in your case, looking at your picture, it is so close to the shower head that it is liable to be splashed.

"Are 230 V extractor fans permitted in zones 1 and 2 of a room containing a bath or
shower?

Yes, a suitable 230 V extractor fan may be installed both in zones 1 and 2, and outside the
zones. If an extractor fan is installed in zone 1 or 2 it must be protected against the ingress of
moisture to at least IPX4 and be suitable according to manufacturer’s instructions. Regulation
701.512.2 requires that equipment exposed to water jets (for example, for cleaning purposes),
shall have a degree of protection of at least IPX5."

Mine is.

 

[Taylortwocities]

Maybe no one has mentioned it is because it is not true.

Ahh...230v fan is ok providing its IP44. Too much wassailing last night.

 

[opps]

Given that the fan is primarily for venting out steam rather than "smells", I would consider a fan with an inbuilt humidistat rather than a fan with on over run timer that only operates when the lights are turned on.

We have a 100mm Manrose humidistat fan that has served us well for the last 6 years. It turns on and off automatically as needed. I have fitted a couple of Vent Axia humidistat fans though that were less reliable, by that, I mean that they were difficult to set so that the shower steam would trigger it but not the rain outside on summer days.

 

[Mottie]

Our fan is wired so that it comes on automatically when a certain level of humidity is reached. It also has a run on timer which I have wired through a separate pull cord next to the wc for obvious reasons. A quick pull of the cord to turn it on, one more to turn it off and then the timer kicks in. I didn’t want the fan coming on every time the light was switched on as it would be venting the warm air every time you went in to have a pee or brush your teeth. Been working fine for years although once a year I remove the cover and clean all the fluff and dust out of it with a dry paintbrush. I don't know whether it will be suitable for your setup though. It’s this one.

 

[Taylortwocities]

Mottie , that’s not a humidity Fan.