Kitchen extraction - reducing NVH - would this work?

[dormermike]

HI

I'm having a new kitchen and thoughts have turned to extraction secondary to the recirc which will be built into the hob, and i'm thinking of using accoustic flexible ducting (from TLC) in the ceiling void, with a basic face plate mounted in the ceiling, and the actual fan in the eaves (am in a bungalow) so the overall run would be approx 4m, but the fan itself is not in the ceiling but mounted at the "exit" pulling/drawing/sucking air through a dumb face plate in the ceiling via the ducting. Idea being i can use a bigger motor/fan, and also mount it directly to joist and vent via sofit, with rubber mounts etc. Mounted in ceiling tend to be noisy in my experience.

So basically instead of this:

(external) | ~~~~~~~~~~~~~4m~~~~~~~~~~~~~~~motor/fan~| (kitchen)

do this:

(external) |~motor/fan~~~~~~~~4m~~~~~~~~~~~~~~~~~~~~| (kitchen)

Is this OK to do, any downsides?

Thanks

 

[jj4091]

Only down side is it will take milli-seconds longer to start extracting when you first switch it on. Why can't you vent the one you are going to have in the hob.

 

[dormermike]

I don't have the space or time for a channel to be dug from the island that the hob will reside on, unfortunately, and also there would nowhere outside for it to vent to, or v limited anyway, due to external ground level.