I have a bathroom that needs ventilating, ideally an electric fan that can take all the moisture and steam away, as at the moment when someone has a shower the steam goes everywhere and is causing damp patches.

However, its not that simple - when is it?!

The bathroom is internal, the door opens into the hall and the walls back onto the kitchen, lounge and bedroom.

Its a ground floor flat, with someone else above!

I don't live there so its not as simple as saying open the door / window in the hall.

The one thing it does have is a ventilation tube, which clearly doesn't work very well.

My thoughts are currently:

1. Get a ventilation fan that has some sort of extender tube that I can run up the existing air ventilation tube.

2. Get a ventilation fan that has some sort of extender tube that I can run through the kitchen wall across the cupboards and out the external.

Now I appreciate that these are very similar responses, but I am not sure what else to do.

Any ideas?

Thanks y'all

I think 1 or 2 would work fine.

HTH

I think you might need to pump some dry air that isn't full with moisture IN to the room to get the damp air out of the room through an extractor. If you have floor boards then running something under them into the room (at the bottom) would be a good start.

Another option might be a heat recovery system might be a way of doing that. I have no idea how cheap/expensive or even if you have the room to achieve that.

I have found this unit which is sort of what you want.

http://www.i-acs.co.uk/store/14110010-hr100s.html?gclid=CPGFiNjKoLoCFUGd4Aod038AIA

Cold showers?

or this one

http://www.vent-axia.com/range/hr100rrs.html

Hmmm your going to struggle. If there is an existing vent tube then try and use that. The issue is these fans are really not that strong. A proper vent system / tube in a block of flats should have many many fans further down the line to assist in moving the air.

I would assume that's what there is in the existing vents. If you run your own vent through the kitchen you will probably have to have an inline fan within that as well.

Get an inline fan:-
http://www.tlc-direct.co.uk/Main_Index/Ventilation_Index/4_Inch_Fans_Duct/index.html

J

Something like this should do the job if you can hide it somewhere and vent to the outside. The key figure is the airflow measured in m^3/hour. Try and get the internal vent as close to the shower as possible and use the timer to keep it extracting for at least 5 minutes after using the timer function. The fewer bends in the ducting the better. I wouldn't worry too much about heat exchanging as it will only be on for a short while.

Or... to save the ballache of all that work and ugly ducting going through your kitchen have you thought about a simple bathroom dehumidifier? You can even get ones that you plumb into the bath or sink waste so you don't have to keep emptying them out. You could also set it to a timer so when the shower is turned on (if its an electric shower) the dehumidifier will turn on and stay on for 20 mins after its turned off or something like that.

Rather than going for a timer I would consider using some kind of humidity sensor to operate whatever mechanical extractor or dehumidifing method you choose.

Thanks all, some useful links there..

I am not sure I want to go down the route of humidifiers and sensors, this all looks very costly, and as this is just a rented flat, cheep and cheerful is my outlook, but one that does the job..

I'm popping there tomorrow to have a look to see what the shortest route will be to get outside and go from there.

So then to add to this...

The flat is only 5 years old, so still covered by the NHBC, is this something that I coudl claim against. It would appear to be a design fault / building error.

Any ideas, links, etc?

Thanks, as ever, y'all guys

Im an air conditioning and ventilation engineer, your best bet is to get an inline fan similar to suggested above and run it to the existing vent duct. This could either be powered by the lights coming on, or a PIR (easy to install movement sensor). You will want to fit a punker louvre above the shower, they are the neatest solution. You will want to make sure that whatever you choose has a run on trickle feature to remove moisture after the lights/PIR signal stops, and 5 mins should be ample unless it gets super steamy in there.

Its a pretty simple installation (dependant on access and bathroom layout) but definately a DIY ok fit apart from the electrics unless you know what youre doing.

Unlikely youll get anything from it only being 5 years old, as they have provided an air path with the window.

Dehumidifier would be unnecessary for what you are after.

Hope this helps, any questions just ask.

Electrics will require a part P certification, no? Unless they're all outside the bathroom.

Cant help with electrics, I just set all the equipment up!

I won't be doing the work myself, I'll get a qualified spark, just wondered what my options were.

Having looked, the only real / easiest option, is to get a fan up the existing vent tube. So am getting quotes on that basis.

Thanks all

If the flat is less than 5 years old then the builder should have provided adequate vent / extract to gain building control approval. I would give them a call and see what they say?

Who says the problem is steam?!

Hello Mr O.

Edited to add. I didn't read the first post...

Thread resurrection - sort of...

Hopefully, Mr O sorted out his damp bathroom woes.

We have just moved into our latest home and it has a small shower room / WC on the lower ground floor (1.95 x 1.25 x 2.35m). Whilst not inherently damp from the surrounding environment, the walls and ceiling are significantly mould-covered and there is clearly a problem with (I would guess) steam-related damp.

There is a reasonable-sized window that opens, but the room is on the ground floor and it is not practical from a security point of view to leave the window open.
There is also a working exterior wall-mounted extractor fan with a timer, but I suspect it is a pretty poor, budget model.

Would fitting a better spec fan make a significant difference to the dampness, or do I need to look at other options?

I guess you have a flush fit axial fan, which is totally inadequate to clear the room.

When I had a new bathroom fitted they replaced my old centrifugal, wall mounted box type fan with a smaller, quieter, flush mount axial fan. Despite being assured it would be "just as good" it was totally rubbish and I had condensation running down all 4 walls when the shower was used.

I replaced it myself with the highest rated axial fan I could find. This was a bit better but still totally inadequate to handle the steam from a power shower.

It was hard to find another centrifugal type fan with the smaller 4" outlet (obviously I wanted to use the existing 4" hole through the external wall) , as most of them seemed to be 5", but I found one eventually.

It has 2 speeds, built in adjustable run-on timer and built in adjustable humidity sensor, the EBB-250N, here:

http://www.solerandpalau.co.uk/docs/catalogo_general/en_ebb_n_fid6815.pdf

keeps the room almost totally clear and is about 3x more powerful than the previous (uprated axial) fan.

Not cheap at about £180, but very effective and the humidty sensor feature is nice where you can switch the room light out and the fan keeps running by itself until the room is clear. The versions without the timer or humidity sensor are a lot cheaper.

Our 4 inch Expelair fan has been fine, the fact that it stays on for 20mins after the switch is off probably has a lot to do with it.

Also do not have the window open and the fan on (the windows should have drip vents, which should be open). The fan should draw warm air from the house and should be in the furthest corner from the door to work effectively

Hmmm. Not sure we can stretch to your Rolls Royce fan, Graham, but thanks for alerting me to yet another thing I had no idea existed - the difference between centrifugal and axial fans. Still not sure I understand the physics, but that's nothing new. As the fan is mounted directly on the external wall (with no ducting), I'd have hoped that a decent axial fan would still do a reasonable job?

bockers, we haven't opened the window as yet, because its location is very vulnerable to intrusion. There are open drip vents though.
The fan is directly opposite the door, with the shower up at the other end of the room, which partially explains why it is not extracting the steam very effectively.