Extractor fan - no backdraught shutter-needed?

[Safety First]

Am replacing a timer only extractor in the bathroom with humidistat version.

The crappy extractor coming out has feeble backdraught shutters that looked to have filled with dust and fluff and stopped working ages ago.

Was looking for Humid' extractor with better backdraught shutters... but the model I most like-best reviews etc- lists on its specs that it has no backdraught shutter?

Are they not ideally fitted? Or do they come as separate items?

Cheers for any input.

 

[JohnD]

I've had good results with cowl vents fitted on the outside wall

https://www.screwfix.com/search?search=cowl+vent

the cowl keeps most of the weather out.

there is one large gravity flap which does not rattle much, or break off like the little venetian blinds on windy days.

Usually available in white, brown or black but can be painted with oil-based-gloss (no primer or undercoat)

 

[Safety First]

Looks good, but my ducting exits downwards through soffits.. shame... as the gravity flap would be very reliable..

 

[JohnD]

You will need a plain grille then.

I think there is a shutter that fits into the duct. Don't remember where I saw it. May have been at a ventilation merchant. IIRC it goes into a horizontal section.

edit
these
https://www.ebay.co.uk/sch/i.html?_...r.TRS0&_nkw=duct+backdraught+shutter&_sacat=0

 

[Taylortwocities]

One of these will do you
https://www.tlc-direct.co.uk/Products/SLSD100CHZ.html
or
https://www.tlc-direct.co.uk/Products/SLSV100CHZ.html

 

[JohnD]

does the shutter operate with a bit of a snap?

 

[Safety First]

does the shutter operate with a bit of a snap?

The shutter was a very thin plastic ring folded along the centre. About as thin as paper, it was coated and weighed down with dust. Also seemed to be fouled on the plastic ducting and also torn, maybe by the wind. The recommended back draft shutter type that I have ordered-the type recommended in replies to this post, seems to look more solid and will be sited clear of other parts. Am replacing timer with humidistat version as timer was never long enough. I am ready for the torture and disappointment of humidistat fans that do not work well. Just hope I get lucky!

 

[EFLImpudence]

Am replacing timer with humidistat version as timer was never long enough.

You may have more fundamental problems, then.

 

[Safety First]

You may have more fundamental problems, then.

You never think it will happen to you...
And those (positive) reviews; the cannot all be made up, can they?

 

[Doggit]

Think about fitting an Airflow Icon fan with a proper built in shutter, and then fit a cowling on the outside. You need to check the wind direction as well, as very few shuters will work if the wind direction is straight on to them, even with a cowl.