brightspark
Member
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- yarm stockton on tees
the envirovent have the back draught shutters built in https://www.google.co.uk/search?q=e...AMO8QXK-0y5_F17qpIHAjEyoAf7YQ&sclient=gws-wiz
- Thread starter Joe 90
- Start date
It's just a thin plastic sheet/flap at the rear of the motor, not the most effective, or at least wasn't for us. Combined with a gravity flap seems to do the job though.
pedrobedro
Man at Matalan
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- 12,984
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- CX near Chesterfield
Exhaust flapper is my solution for the one on our cooker hood, it's a bit noisy in high winds though.
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- 14,543
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- UK
Had a similar issue, the ensuite from our bedroom is on the gable and the wind whistles past. I'd previously fitted an outside grill with flaps to try help solve it but that just rattles when the wind blows.
Fitting this type of fan with a 'front cover' rather than just an open aperture seems to have done the trick. I took the rattley grill off and put the original one back on too.
Fitting this type of fan with a 'front cover' rather than just an open aperture seems to have done the trick. I took the rattley grill off and put the original one back on too.
DAPPH
as dyslexik as I'm daft
- Messages
- 7,169
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- Near to Cross Hands Llanelli SouthWales GB
They are fantastic , make sure you use decent wall plugs in carefully drilled clean holes by using two or more drills to get to the optimum sized hole and use stainless screws so in 10 or so years you can unscrew the worn out one and fit a new one easily as you'll be ten years older when on the ladder .
Kram
Member
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- 7,104
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- Sussex
Oi Im still in my 30's 
Common masonary drills , which is what I used, do not like following and enlarging existing holes. The hole quality will be much better using a 4 flute masonary or even a diamond segment drill.
What?! We are talking about a vent cover with bog standard 6mm rawl plugs.
Common masonary drills , which is what I used, do not like following and enlarging existing holes. The hole quality will be much better using a 4 flute masonary or even a diamond segment drill.
rtcosic
Member
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- 2,823
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- Warwickshire
I had this type:
It rattled annoyingly in the wind. I carved a recess in the flap and the frame, then glued a piece of steel in the flap recess and a very small magnet in the one in the frame.
The magnet was strong enough to hold the flap shut in the wind but weak enough that the cooker hood overcame the magnetic force. I experimented with a few magnets held in with blue tack before settling on the final one.
It was quite noticeable that the fan ran for a few seconds before the flap popped open.
It rattled annoyingly in the wind. I carved a recess in the flap and the frame, then glued a piece of steel in the flap recess and a very small magnet in the one in the frame.
The magnet was strong enough to hold the flap shut in the wind but weak enough that the cooker hood overcame the magnetic force. I experimented with a few magnets held in with blue tack before settling on the final one.
It was quite noticeable that the fan ran for a few seconds before the flap popped open.
Has anyone tried one of these outside covers.
pedrobedro
Man at Matalan
- Messages
- 12,984
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- CX near Chesterfield
My vent in the shed has a slightly larger 1/4" thick pvc sheet fastened over the outside with half inch spacers to stop direct draughts as it is over the bench, not one of my better ideas putting it there.
DAPPH
as dyslexik as I'm daft
- Messages
- 7,169
- Location
- Near to Cross Hands Llanelli SouthWales GB
I like that idea , perhaps using sticky strip low grab magnetic strip , clean the surfaces with isopropanol and using a plier type hole punch pop out plenty of round magnets site them opposing each other to get a light grip .
