Installing extractor fan in bathroom

[NBee]

Hi all. We desperately need an extractor fan in our bathroom, and I'm just doing some research to find out what type of installation to go for.

It's a top floor maisonette with a tradition timber framed pitched roof, and solid brick walls. So I guess the options are

a) wall mounted fan which goes through the solid wall
b) ceiling mounted fan which goes through the plasterboard and is then ducted to the eaves which are around 2m away.

Which would be the simplest to install? Is there any reason why I should go for one type and not the other?

Also, I'm probably not going to do this myself - depends if I have the time and inclination. If I search for someone to do this, what type of tradesperson should I look for?

Many thanks for any advice!

 

[JohnD]

if you get a loft-mounted inline fan, it can be more powerful and quieter than a wall fan, especially if you mount it on a piece of ply padded with synthetic carpet.

It will be bigger and unsightly, but that won't matter in the loft.

Use rigid duct rather than flexible (which traps dust and fluff) sloping it slightly towards the outside for any condensation to run out, and flop loft insulation over the duct to reduce risk of condensation.

 

[foxhole]

Is it hip or gable roof, you have the option to take out thru a gable end [loft] position. Centrifugal fans are more efficient than axial fans and are available for both wall and loft mounting.

 

[NBee]

There are no gables, it slopes down to eaves and gutter on all elevations. Which I guess makes it a 'hip' type?

 

[Ben565]

As JohnD said, an Inline type fan will generally be quieter and more powerful. Use rigid ducting as the ridges in the flexible stuff restrict the airflow. It would also be an idea to insulate the ducting to help prevent condensation developing inside it. You can do this as JohnD said by covering it with loft insulation, or use purpose made foam cladding.

When I had the house rewired the electricians put in a ceiling mounted fan, which was feeble, hardly shifted any air, and resonated loudly on the ceiling it was mounted to. I replaced it with a loft mounted Vent Axia inline fan, with Vent Axia humidity sensor. I used rigid ducting and Domus Thermal duct insulation. I can't honestly say it was cheap! but really very pleased with the performance and quietness of the setup.

Vent Axia aren't the cheapest brand around but I have been very pleased with both their products and their after sales support has been first rate too. When I clumsely broke part of the fan unit they were really helpfull and had a replacment part delivered to me by the following afternoon.

 

[Ben565]

You can get vent tiles to provide an outlet for the fan.

 

[NBee]

Thanks for the replies.

In actual fact, we had a builder take a look who was doing some work for the neighbour. I'd forgotten that we have one of those vents in the external wall with a grill covering it. When I decorated years ago, I actually filled in the vent and painted over it (goodness knows why!).

So I think in this case it would actually be easier to mount the fan on the wall, as there is not as much builders work required to make the hole. Does that sound sensible?

 

[JohnD]

yes, but if it does not already have one, fit a plastic duct and a cowl vent, or you will get condensation in the brickwork. The should be no gaps allowing steam to blow back in.