Rattling Vents

[imroberts]

I have cowled vents on both my bathroom and kitchen fans. They're both on the same side of the house and have been rattling really badly with the wind over the last week.

I was wondering whether it'd be worth replacing the cowled vent with a standard louvre (with or without flyscreen - particular in the kitchen fan this seems like it must just get clogged up with grease and make the fan less effective?) and fitting an inline back draught shutter instead. The bathroom fan has quite a lengthy vent in the loft so I could fit the shutter quite some way from the outside if that was likely to be beneficial.

Firstly, is an inline back draught shutter likely to remove the problem, or is this likely just to rattle instead?

Secondly, if I go with this approach, where exactly should it be mounted? In the case of the bathroom fan which is an in-line type, I assume it should go between the fan and the outside, but should it be as close to the fan as possible, as close to the outside as possible, or somewhere in the middle?

Thirdly, can anyone recommend a good quality back draught shutter? I've noticed some reviews criticise the springs as being inadequate and the flaps never closing entirely, though I guess there's a limit as to how strong it can be or the fan won't be capable of opening it?

Alternatively, any other suggestions for me?

 

[GoodDIYjob]

1. Yes, I would say it will be better protected from rattling.

In our bathroom, when the wind is gusty you can here the backdraft valve swing but the kitchen shutter vent will be going mad clicking open and shut.

2. Yes, after inline fan before exhaust outlet.

3. I used a plastic one, but you can also get metal ones, they are mostly (perhaps all?) unhinged AFAIK to reduce flow resistance when operating.

More difficult to incorporate into a kitchen hood, depending on how much room you have to work with behind the cooker hood spigot and the core exit for the pipe.

https://uk.rs-online.com/web/p/back...bMkvNbT1r-2H1zMrFPxoCMj0QAvD_BwE&gclsrc=aw.ds

 

[imroberts]

2. Yes, after inline fan before exhaust outlet.

Cool. The bathroom outlet has a coupler already in the pipe which is roughly halfway from the fan and the outside grille, looking at it I should simply be able to swap out the coupler for the backdraught shutter without altering anything else.

3. I used a plastic one, but you can also get metal ones, they are mostly (perhaps all?) unhinged AFAIK to reduce flow resistance when operating.

I'll probably get a metal one. It definitely feels like they should be longer lasting.

More difficult to incorporate into a kitchen hood, depending on how much room you have to work with behind the cooker hood spigot and the core exit for the pipe.

I've had a look inside the kitchen hood today and there's actually a set of butterfly flaps on top of the fan unit where the hose attaches. So for that one I think I'll just buy a louvre vent with flyscreen for the outside and be done with it!

 

[foxhole]

If you clean the grease filters then no grease can get beyond them to fan and outlet?

 

[GoodDIYjob]

When I said "unhinged" I meant unsprung..... If they have springs to overcome they will provide resistance to airflow depending on whether the hinge resistance is to closed or open default. It would affect either shutting to gusts or opening for exhaust air.....

 

[GoodDIYjob]

Cool. The bathroom outlet has a coupler already in the pipe which is roughly halfway from the fan and the outside grille, looking at it I should simply be able to swap out the coupler for the backdraught shutter without altering anything else.


I'll probably get a metal one. It definitely feels like they should be longer lasting.


I've had a look inside the kitchen hood today and there's actually a set of butterfly flaps on top of the fan unit where the hose attaches. So for that one I think I'll just buy a louvre vent with flyscreen for the outside and be done with it!

Yes, I've seen some hoods with those. My cheapie hood doesn't, but with yours it should be ok.