Help!! Downstairs Bathroom Extractor fan through Flat roof

[c0nfused]

Hi,

I am installing a Extractor fan in my downstairs Bathroom, it will be going through a flat roof.

Ok i have a got the following:

100mm DIA PLASTIC ROOF VENT COWL FOR 110mm PIPE

110mm pipe

100mm Ducting

100mm Fan

My question is how do i attach the 100mm Ducting to the 110mm Pipe??

Also is there anything else i will need?

Any help would be appreciated as i am not very experienced in this type of thing

 

[JohnD]

it will be going through a flat roof.

Why?

It will probably leak

 

[c0nfused]

Well the reason i am asking is so it is done properly & hopefully wont leak!

But thanks anyway.

 

[JohnD]

have you already got a hole in the roof? You need a special collared tile to seal the pipe to the roof coating. It is roofer's work and I can't help with this. Even if a roofer does it, it is more likely to leak than a roof without a hole in it.

have you got an external wall or window in the bathroom?

 

[c0nfused]

Hi thanks for taking the time to reply.

There is no hole in the roof at present, i cant go through the external wall because it has just been finished, but i do have a small window.

Any thoughts?

 

[freddiemercurystwin]

You've also not said what the flat roof is finished with. Regarding sealing the penetration you'll probably get a better response in the roofers section, not sure the roofers on the Forum check here. As JD says a wall vent would be best but if that can't be done there is more chance a roof leaking with a hole in it than not but there is no reason for it to leak if it is properly done.

 

[JohnD]

If it was me, I would hire a core drill for half a day. It will easily drill a neat, round, 110mm hole through the wall. This is the way I would recommend. If the wall is tiled, you can expect to replace the tiles you drill through. If it is plastered and painted, and you drill from both sides, it might not need redecorating at all.

a second choice would be to fit a window fan. You will have to get new glass cut.

If you are not a skilled roofer, making a hole in the roof is a very bad idea.

 

[c0nfused]

Thanks for your replies, i do appreciate it.

I do know people who can probably do this for me but i will need to make sure i have everything ready for them.

Do you know how i attach the 100mm Ducting to the 110mm Pipe??

Do i need a part ie: a reducer or do people just tape it?

Thanks!

 

[JohnD]

I think this one is to connect two pipes both with an internal diameter of 100mm
http://www.screwfix.com/prods/12697/Heating-Cooling/Ducting/Manrose-Round-Connector-100mm

there are more on http://www.screwfix.com/search.do;j...search=duct&searchbutton.x=6&searchbutton.y=7

 

[c0nfused]

Thanks John that's brilliant

 

[foxhole]

I ran my kitchen vent out thru the flat roof space, avoids going thru wall or roof.

 

[freddiemercurystwin]

I ran my kitchen vent out thru the flat roof space, avoids going thru wall or roof.

It must exit to the open air via a wall or a roof though?

 

[big-all]

i am worried here
you have purchased a roof mounted fan with a cowel specificly for roof mounting!!

 

[foxhole]

I ran my kitchen vent out thru the flat roof space, avoids going thru wall or roof.

It must exit to the open air via a wall or a roof though?

Over the wall, under the roof, THE EAVES.