Air vents one way.

[footprints]

I have an old flue I want to vent in the loft, but I don't want dust and debris to blow back when the wind is unusual. I want to put a vent in the stack facing the west which is the usual wind direction but avoid muck getting blown out of the vent on the odd day the wind is easterly.
A bit like the old mica flaps the used in drain vents way back.

The normal gravity flap vents operate the wrong way they would need to be on the inside of the flue.

I have looked at anti back-draught in line vents but they usually have springs to operate with a fan, any ideas for a solution please?

Thank you,
footprints

 

[^woody^]

Search for passive vents

 

[footprints]

Search for passive vents

Thanks woody I'll give that a try later.

 

[Tigercubrider]

Take the springs out?

I had a one way flap that was centre pivoted and there was a bolt through a hole to. Bias the CoG so it shut

 

[footprints]

Take the springs out?

I had a one way flap that was centre pivoted and there was a bolt through a hole to. Bias the CoG so it shut

Yes something I was thinking about, it means obtaining one to try it out, I was thinking of making a vent with a flap up or reversing an extractor vent with flaps and fitting it wrong way around to the wall with a spacer of some sort.
Seems strange there are not fireplace vents with a little flap built in to stop draughts down an unused flue.

Mmm Tiger Cub that brings back memories, the first bike I had was a 66 Tiger Cub which had the Bantam frame in blue and white, lovely little bike.

 

[footprints]

Found a 100mm gravity back-draught damper on Amazon might do the trick as I have a 105mm core drill, but still open to any ideas as that would still need a louvre of some sort to discourage pests.

 

[^woody^]

If you take the spring out, and rely on gravity it will be bang bang banging away with every bit of draught and pressure change

 

[footprints]

If you take the spring out, and rely on gravity it will be bang bang banging away with every bit of draught and pressure change

True, not sure if I would hear it there though.