What can be done to stop drafts from extractor fans?

[Joe 90]

I have a fairly new build that's well insulated but the drafts from the extractor fans has always annoyed me.
Every bathroom fan and even the cooker one. We live in a very exposed area with a lot of wind. Some vents go out to the fasia, some go straight out the wall, it doesn't seem to matter. What options do I have.
Is an inline back draft excluder a good job and where do you put it, at the fan or the vent?
Is expensive fans which close up when not in use a good job and do they last?
What's the best vent on the outside of the wall in a windy area?

Airflow iCON 15 Extractor Fan - 100mm/4",Energy Efficient 9.4W, Quiet Iris Shutter, IPX4, Wall/Ceiling Mount, 19 l/s Airflow, Multi-Control Options, 3-Year Warranty, Building Regulations Compliant https://amzn.eu/d/56mr2az

 

[JOEPRO]

I believe there are anti backdraught outer wall covers available, I would go for one of those by vent axia, glidevale or other reputable manufacturer.

 

[Morrisman]

Remember, when a fan is running it has to get its air from somewhere. In my bungalow the bathroom fan makes a groaning warble when it’s on, if I don’t have a small window cracked open nearby. No problem in summer, but the other 50 weeks of the year I tend to keep every window shut up tight, so I leave the kitchen window open a 1/2” so the bathroom extractor sucks from the kitchen, directly across the hallway.

 

[Kram]

If the fan has a reasonable pressure, I'd recommend this. Its not going to open with a cheap bathroom fan though. My video in the review. Works great for a powerfull cooker hood fan.

https://www.amazon.co.uk/dp/B0CN37B198

 

[Erie Fred]

Would a simple exhaust flapper work like for a clothes dryer ?
https://www.homedepot.com/b/Heating...ode+matchpartialmax&NCNI-5&visNavSearch=dryer vent

 

[GRW]

Passive, top hung lightweight louvres can work with the fan pressure being enough to lift them.
The downside with such low power fans is that external wind force might be too much for the fan pressure to open them when needed.
Not the prettiest possible solution would be to have diverting plates spaced out in front of the e ternal fan outlet. These can alleviate direct wind pressure into the fan outlet, but allow unrestricted access for fan pressure air to disperse around the diverted plate horizontally.

(I hope that explanation makes sense!)

 

[colnerov]

Would a simple exhaust flapper work like for a clothes dryer ?
https://www.homedepot.com/b/Heating...ode+matchpartialmax&NCNI-5&visNavSearch=dryer vent

Home depot don't want us to see it, (access denied).

 

[Anguz]

the icon fans are good. got one in the bathroom... no noticeable draught and i have not got a flap on the outside
fitted a new one just before xmas, as the bearings had gone in the old one after about 5 years
direct swap, and reused the timer module

 

[jsf55]

USA site

 

[Joe 90]

If the fan has a reasonable pressure, I'd recommend this. Its not going to open with a cheap bathroom fan though. My video in the review. Works great for a powerfull cooker hood fan.

https://www.amazon.co.uk/dp/B0CN37B198

Does it rattle when it's windy

 

[Kram]

No I havent heard any rattling yet.
The only minor issue, due to my lazyness to get ladder out and grease the pivots - do this before fitting. Is that on low power, where the flaps flutter a bit, they currently squeak. A dab of grease will solve that but cant reach..

Edit to say this was to replace a wickes plastic one. Plastic ones seem to fall apart after only a year or two.

 

[Jasper42]

I have the below fitted in the attic for the bathroom

Link

And one of these for the kitchen Link

 

[gaz1]

to be honest they dont work that well you will always have a draft and that room will always remain on the colder side thats the issue of drafting direct to the outside from showers or from cooker hob units

any vent high will always let hot air out of the building so your wasting heat from the house

you can preheat the incoming air though

if you went the channeling method so the air is preheated then the tubes tend to cause a sound when air is traveling through them

 

[brightspark]

I have a fairly new build that's well insulated but the drafts from the extractor fans has always annoyed me.
Every bathroom fan and even the cooker one. We live in a very exposed area with a lot of wind. Some vents go out to the fasia, some go straight out the wall, it doesn't seem to matter. What options do I have.
Is an inline back draft excluder a good job and where do you put it, at the fan or the vent?
Is expensive fans which close up when not in use a good job and do they last?
What's the best vent on the outside of the wall in a windy area?

Airflow iCON 15 Extractor Fan - 100mm/4",Energy Efficient 9.4W, Quiet Iris Shutter, IPX4, Wall/Ceiling Mount, 19 l/s Airflow, Multi-Control Options, 3-Year Warranty, Building Regulations Compliant https://amzn.eu/d/56mr2az

there expensive and the automatic shutters soon get clogged with talk dust and moisture .get a decent envirovent timer fan for about 45 quid 5 year warranty on em silent running ballbearing motors and high flow rate

 

[brightspark]

I believe there are anti backdraught outer wall covers available, I would go for one of those by vent axia, glidevale or other reputable manufacturer.

they all tap like a letterbox when its windy on a gable end you can fit a one way shutter in the 4 inch pipe if its inline. much better than the outer grill ones and dont tap

 

[winchman]

Our kitchen fan has a backdraught shutter, opens when fans on closes when off, works fine

 

[voipio]

The external type flaps can flap quite a bit during strong winds, and need a bit of damping. I've used Trybosin 320 Blue viscous grease on the hinges, which works really well and makes the flaps open and shut gracefully. The trouble is the viscous grease doesn't stay where it needs to be for long, so the benefits don't last, and re-application of grease is necessary.

The viscous damping grease trial pack from Newgate Sims is a useful thing to have. I have no links with the company.

Tribosyn Archives - Newgate Simms

shop.newgatesimms.com

Another thing I've done, in a room that doesn't suffer from humidity/condensation, is to take a block of polypropylene packing foam, cut to size, pressed hard against the grille, and then cuts, about 6-7mm deep, carefully made using a carving knife, along the faint indentations made by the fins, plus removing a bit of foam in the middle (which doesn't show up very well in the image). It fits really snugly, even on overhead fans, and makes quite a difference.

 

[Gregb23]

they all tap like a letterbox when its windy on a gable end you can fit a one way shutter in the 4 inch pipe if its inline. much better than the outer grill ones and dont tap

I went with inline 4inch gravity shutters, reduce to fit inside the 4 inch pipe, with small weights attached. Without the weights would clap madly in the wind, even with a multitude of different cowls. Very exposed here, but has now fixed the issue nicely.

 

[Gareth J]

If you are in a windy spot, gravity backdraught flappers work to keep wind from coming in but not to stop negative pressure drawing air out. And they flap and clatter as gusts alter the pressure around the house. With that in mind, if you fit them, keep them as far out as possible.

I wouldn't put the external Louvre type on there, they clatter even more and fall off pretty quickly in windy spots.

The best are the servo actuated ones that come within a fan. They seal better, don't flap and I've not had one fail. There are a few here, one was put in 10+ yrs ago I'm sure.

Mushroom shaped external vents may help slow the wind's oomph. Not sure about that though.

 

[Joe 90]

there expensive and the automatic shutters soon get clogged with talk dust and moisture .get a decent envirovent timer fan for about 45 quid 5 year warranty on em silent running ballbearing motors and high flow rate

Is this the one your talking about? And am I right in saying it has a build in draft thing that will stop a draft?