Please recommend a bathroom fan that will help with condensation in flat

[JohnD]

I haven't seen your duct. It is quite likely 100mm (four inches) but might be 125mm or 150mm. Bigger is better.

 

[chaletstyle]

this one is about twice as powerful as a typical cheap bathroom fan. It would have to go in the boxing-in you mention, because it is bigger, which will need a hatch for access to install and for maintenance.

You had better find out the actual duct size before you buy it. If you find it is 5 or 6 inches you can have a bigger fan.

Instead of a humidstat, get this one which can be wired to come on when they turn on the light, and adjust the timer for a 20 minute run-on. You say it is an internal bathroom so I guess no windows so the occupiers will probably turn on the light every time they use the room, so you are not dependent on them making a conscious effort.

It is very quiet and economical on electricity.

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

Thanks for the tip.

 

[chaletstyle]

I haven't seen your duct. It is quite likely 100mm (four inches) but might be 125mm or 150mm. Bigger is better.

My comment was to Iggifer

 

[Dart]

Hi
Dampness can be very expensive to eradicate, fans remove condensation as well as heat from a building, it seams you have condensation in more than one room. I would fit a time controlled fan in the bathroom, if you fit a humidistat controlled fan it may run for ever taking what heat you have in the building. A dehumidifier can help in the short term it also puts heat into the building as well as removing the condensation, but can be expensive to run. The only long term solution is to improve the insulation. You may also have dampness traveling from the outside to the inside of the building this needs to be stopped.
Standard tumble dryers create a massive amount of condensation, a condensing version may help. A cloths Boiler creates large amounts of condensation. An open vented heating system can also be a problem.
Dart

 

[EFLImpudence]

Ah. You didn't say it was rented.

Then you need new tenants. They will not change.

I have experience of renting flats and I have said before, the same flat can be a mold ridden mess or a little palace depending on the tenants.

 

[chaletstyle]

EFL: To be fair to the tenants, the building is more prone to condensation because of lack of roof ventilation and cold walls.

We do need better tenants though next time. Currently empty.

Thanks Dart: There is certainly no penetrating damp from outside. By having better extraction it will help. I think if i get in on low continuous we can make an assessment to see what happens and change if necessary.

I'm having the whole flat cleaned and repainted for a fresh start

 

[Dart]

Hi
When you redecorate why not use a special paint, a little bit more expensive but may work. Check out with paint manufactures.
I used a special paint along with dehumidifiers set to about 85 % relative humidity condensation piped to a foul drain. It worked for me on a large project.
Dart

 

[wundaboy]

I've had great success with one of these in a house which previously suffered chronic damp due to a variety of factors. We tried loads of different things and this finally fixed (masked?) the problem very successfully. It has to go in the loft though and is quite expensive.
http://www.nuaire.co.uk/products/catalogue/residential/positive-input-ventilation-piv/drimaster/

Or there's this for situations where there's no loft or access to the loft is not an option. Unlike the previous one, this one needs venting to the outside though.
http://www.nuaire.co.uk/products/catalogue/residential/positive-input-ventilation-piv/flatmaster/

 

[chaletstyle]

Hi Wundaboy
Thanks for your experience
I have seen those advertised. They work on fresh air continuosly being forced into the building via a duct and then stale air being forced out through gaps in the fabric of building.

Wheras an background extractor sucks air out of the building through a duct and the air to replace it will come from holes and gaps in the building

So they basically do the same thing except the direction of air flow is in the opposite direction.

As it would be far easier and cheaper for me just to replace my poorly performing bathroom fan with current duct set up with a fan that is stonger and can work in the background 24/7 without too much agro, I will probably try that first.

 

[ban-all-sheds]

If you suck more air out, where will the air to replace it come from?

 

[chaletstyle]

If you suck more air out, where will the air to replace it come from?

Under doors, through micro holes in the fabric, cracks in the loft hatch, also considering retro installing a trickle vent in the double glazing of 1 or 2 windows.

 

[ban-all-sheds]

And where will the air going under the doors, through holes in the fabric, from the loft, and through trickle vents in windows be coming from?

 

[chaletstyle]

And where will the air going under the doors, through holes in the fabric, from the loft, and through trickle vents in windows be coming from?

Outside....

 

[EFLImpudence]

 

[JohnD]

Maybe he lives in a hermetically sealed submarine, underwater, in which case an extractor fan would not work?

If, however, he lives in an ordinary house, it will.