Extractor Fan - ducting leading to boxed in Ply to outside

[dazzlerpalmer]

Gentle Men - (and ladies)

I am in the process of replacing an extractor fan (wall mounted) in my downstairs shower room. I am going to us a Greenwood 100m fan and vent it out the wall.

When I removed the old fan I noticed that there was a length of pipe about the length of the wall cavity and then a boxed in section of ply that runs through the width of the attached garage to an air brick.

Can I just sit the new fan straight onto the pipe or will I need to somehow connect a flexi hose to the airbrick? The total run is about 3 meters.

It will be a nightmare if I have to remove all the boxed in section cos it is up high in the garage and behind a fixed structure.

Any ideas?

p.s. at the moment I have not noticed any damp anywhere in the garage.

Cheers

 

[daytona]

when i fit all mine,if its an axial fan without some sort of shutter on it ,i will cut a backdraft shutter inline(when it goes into an airbrick)and duct the full run.3m flexiduct run not a great idea tbh use solid duct.are you sure the fan can extract properly.the moisture isnt just sitting in the pipe is it?

 

[daytona]

you could feed sections of duct(if solid)through the existing hole in the cavity for the fan and join the pieces together as long as its not all in silly short pieces,depends how much room you got

 

[dazzlerpalmer]

I would have thought the boxing in would lay wet but it appears to be dry.
It is not a power shower though so it's not as if there is loads of steam belting out.

It seems a crappy idea to me. The small bit of pipe is just so it does not vent into the cavity but from then on its just ply wood for 3 metres.

 

[RF Lighting]

Could you slide a single length of solid duct (or soil pipe) down the boxing from outside inwards?

The rough a*se kitchen fitters ducted my cooker extractor with some bits of kitchen cupboards

 

[securespark]

Quality joinery!

 

[dazzlerpalmer]

I have decided to rip all the ply boxing away and put in a pipe

thanks

 

[baldelectrician]

could you feed a bit of trunking lid in at one end and tape flexihose on to it?

this may give a solution.