HawthorneVillager.com

This happens all the time. The vent on the side of the house for the over the stove fan has flaps on it that bang open and closed in the wind. It sounds like it is coming from your microwave because the microwave is vented through those flaps.

Yes this is normal (although can be somewhat annoying when it's windy). Most rangehoods will also have a damper flap on the other side of the fan - this is likely what you're hearing. The vent flaps outside (on your exterior wall) may make some noise as well.

There are different vent covers available that do not make this racket, but heaven forbid, they cost the builder a couple dollars more.

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For Home Inspection services call Andy Shaw at Halton Home Inspection Service. 905 876 4761

That's what I've been saying (above). I think you guys will be in for an interesting surprise when you replace your exterior vent cap and still hear exactly the same popping sounds when it's windy...

It's easy to determine which vent is making the noise. Usually the kitchen's exterior vent is somewhat accessible. If you can't reach it, then just get a broom or something and hold it against the flaps on a windy day. Someone from inside can tell you if the sound stops or not.

From my experience, most of the time it's the exterior flaps making the noise.

Andy Shaw - 905 876 4761
Halton Home Inspection Service
http://www.haltoninspections.com

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For Home Inspection services call Andy Shaw at Halton Home Inspection Service. 905 876 4761

You need to hold exterior flaps in the open position. That will allow the air flow into the vent to disturb the damper inside.

My thinking is that if the exterior flaps stay shut when the fan is off, then the other flap will not make noise anyways.

After all, the inside damper, if there is one, is only making noise because wind is getting in from the outside vent.

Andy

_________________
For Home Inspection services call Andy Shaw at Halton Home Inspection Service. 905 876 4761