Bathroom Fans

[jamesbates87]

Hi,

Hoping someone could give me a bit of advise on the below.

I have a two bedroom terrace house, that has a bathroom on the top floor in the middle of the two bedrooms. At current I have a bathroom fan located in there that works off the light and stays on around five minutes after the light is switched off. The problem that I'm having is that it is doing enough, as when I'm having a shower the bathroom is very damp, along with the other two bedrooms upstairs. The bathroom fan is very new and got fitted in January 2012.

I believe that the problem is that the ducting that was put in, is far to long for the fan power. The ducting goes from the fan towards the back of the house. Traveling around 5 - 7 meters.

What I was looking at was, buying a "In-Line" fan and placing this half way between the ducting to help with the flow of air. Would this would a good thing?

The only other thing would be to buy another fan and place it into the bathoom then join them both up and a "In-Line" fan that helps both of them.

Any help would be great.

Thank you

Jimmy

 

[ban-all-sheds]

when I'm having a shower the bathroom is very damp, along with the other two bedrooms upstairs.

It's worrying that the bedrooms get damp as well...

The bathroom fan is very new and got fitted in January 2012.

Who fitted it?

Were they asked to provide a ventilation solution? i.e. can they be held responsible for lack of performance?

I believe that the problem is that the ducting that was put in, is far to long for the fan power. The ducting goes from the fan towards the back of the house. Traveling around 5 - 7 meters.

The length, and type, of ducting, number of bends etc, need to be taken into account when deciding how powerful the fan needs to be.

Also, is there a gap under the door to allow the fan to draw air into the room?

What I was looking at was, buying a "In-Line" fan and placing this half way between the ducting to help with the flow of air. Would this would a good thing?

Inline centrifugal fans tend to be more performant for a given size/electrical power, so if you have somewhere to put one then it could be a good idea. But instead of the existing fan, not as well as. Seek advice from the manufacturers on where best to position it along the run of the ducting. Think about access for maintenance, and where the wiring will need to go.

Where is the ducting, BTW? If it's in the loft I hope it's below the insulation, not above, or you'll get terrible condensation problems.

The only other thing would be to buy another fan and place it into the bathoom then join them both up and a "In-Line" fan that helps both of them.

Just replace the existing fan with a more powerful one.

And pay scant regard to the "guidance" on how many air changes per hour you need - go for the most powerful fan you can afford/have space for - I doubt it will cave in the walls/pull open the door/pin animals and small children to the grille.

 

[jamesbates87]

Hi,

1. The bedrooms aren't really damp, just a slight build up of condensation on the windows.

2.. There is a slight gap between the door, I will be looking at that and creating a slight bigger gap.

3. The ducting is running above the insulation. The loft has been insulated I.E with boarding - Does the ducting need to be inside the insulation? I've never read that?

Thanks for the fast reply, it's brilliant !!

Thanks

Jimmy

 

[ban-all-sheds]

Re 3/ - yes, it must be insulated.

You can see that when steamy air hits cold surfaces it condenses, so this will happen inside the ducting when it's cold in the loft.

If the ducting slopes upwards from the fan the water will run into it and knacker it.

If the insulation is good, and it gets really cold, it will freeze inside the ducting.

Who put the ducting in? Or added insulation on the wrong side of it?

 

[Chri5]

Flexible duct such as this

Isn't the best, the ridges allow for condensation traps.

I'd suggest a decent inline fan married to the cubic meters of air in room and the per hour clear through rate. I'd also suggest using rigid duct such as

Or

See a full range of components, ducts and fans here



http://www.tlc-direct.co.uk/Main_Index/Ventilation_Index/index.html

 

[jamesbates87]

Hi,

Thanks for all the replies there really useful. The loft was done before I moved into the house, along with the fan and ducting.

The ducting is the white tuber one and runs above it all. As the loft has been boarded out.

So what do you think is best for me to do now?

Buy rigid ducting and insulate it above? Or take the boarding up and run it within the insulate above the ceiling?

Thanks guys !!