What kind of extractor cover and how do i fix it?

[les_danger]

Hi, apologies if there is another area to post this I feel like i'm probably not using the right terminology so would appreciate any help.

I've had a rewire of the house recently, and we were planning on converting one of the bedrooms to a bathroom in the future, so along with other things we had the electricians put in an extractor fan in the ceiling which then runs out to vent from the gable. They clocked off quite some time ago, but it was brought to my attention that there isn't actually a cover on the hole they've made in the wall to vent out of.

It's quite high but from what I can tell the hole is just over 120mm (125mm/5"?) in diameter. The vent isn't fixed to anything it just seems loose. Nothing's nesting in it yet! The wall is West facing, so I expect I'd need one of those downward facing cowls? Only when I locate those online there aren't any pics of the rear to show fitment.

I have very little DIY experience but keen to give this a go so any pointers on fixing it to the wall welcome. I'm going to try and get up into the loft void where the ducting runs to get a better look and take a measurement from there when time allows.

Thanks

 

[JohnD]

That looks like they have poked flexible plastic duct into the wall.

Maybe you will be able to pull it out enough to fix it to a vent. If not you will need an adaptor, or possibly replace it with rigid duct, which is superior. Tilt it so any condensation runs outwards.

I recommend the Cowl Vent, which has a cover to deflect rain and wind, and an anti-backdraught flap

Cowl Vents | Ventilation | Screwfix

Buy Cowl Vents at Screwfix.com. A hooded vent. Prevents drafts. Suitable for flat or round ducting. Click and collect in hundreds of stores nationwide.

www.screwfix.com

I find the brown one tones with the colour of my brickwork. If you want, you can paint them (oil-based gloss, no undercoat) before fixing.

I strongly advise against the sort with little flaps that look like a venetian blind. They constantly rattle annoyingly, until they break off. Luckily this does not take long.

 

[les_danger]

Thanks very much John. Silly question - so on the reverse of those cowls does it have a circular connection (that I guess would have to be slightly smaller than 125mm so that the flexible vent can slip over it)? Or do have to get the rigid circular bit separately to then plug into the cowl?

Cheers

 

[JohnD]

Yes. Some of them have two sets, such as 100mm and 125mm, and you cut away the unwanted part. The vendors description will say.

The most common size that builders fit is 100mm duct

 

[JohnD]

In this pic you can just see the spigot that pushes into the duct

1240W Weather Proof Cowled Wall Outlet White 100mm/4Inch | Manrose

www.manrose.co.uk

 

[les_danger]

Ah gotcha, thanks for that John.

On some of these pics I can't see any holes for fixing the cowl to the wall, do you just silicone them on? Or drill your own holes in the cowl? Apols, I did say I have next to no experience!

 

[JohnD]

I haven't done one for a long time, but IIRC there is a back plate you screw to the wall, and the cowl clips over it.

 

[les_danger]

Awesome, thanks again!