Kitchen Extractor

[ninapee]

Hi,

Possibly should have already planned this better, however....

I have just knocked into the chimney breast in our kitchen and put our hob and oven there. I would like to move an existing extractor from and external wall to above the hob so it is hidden up inside the chimeny. This will give us more wall space which we are limited on and seems to make sense.

The only thing I'm not sure about is whether venting directly into the chimney is just going to create a damp rank mess inside the chimney hidden behind the boarding. Would I need something to run all the way from the top of the stack down the chimeny to the extractor?

Any help would be lovely!

Thanks,
Nina

 

[timtheenchanter]

IMO you do not need the extractor at all in the chimney, its designed to take stuff up it by natural means, not forced extraction.
my parents had exactly what you describe (except no knocking in was required, it was a huge fireplace) and the natural extraction was plenty.

 

[ninapee]

We have put a board at the bottom of the chimney with spots lights so its sealed at the bottom at the minute anyway??

 

[riveralt]

Most standard axial kitchen extractor fans are limited by the manufacturers instructions to 3metres.
A centrifugal fan allows for distances up to 10 metres and some more.
However couple of issues.

Dust and muck (even old cold dust) will possibly fall down onto fan causing damage.
Also since the majority of the ducting will run vertically you will need a condensation trap to prevent water ingress from above.
You will probably need to get a proper cowell put on the chimney as well.

Are you sure you cannot use the current position or create a new one?

 

[bernardgreen]

We have put a board at the bottom of the chimney with spots lights so its sealed at the bottom at the minute anyway??

The chimney must have some ventilation otherwise damp can accumlate in stack and while it may be apparent in the walls it can lead to mould growing inside the chimney stack.[/quote]

Also have you ensured the changes to the chimney have not weakened the support of the brickwork above the bricks you removed.

I know someone who removed most of the ground floor fireplace without giving any thought to the effect on the chimney stack. The only reason the entire chimney stack did not collapse into the house was that a neighbour was shown the new decor, saw the danger and wedged in supports.

 

[ban-all-sheds]

Surely she would have had to have given details of what would be done to ensure compliance with Part A when she submitted her application for Building Regulations approval, so why should there be any concerns about the structural integrity of the chimney?

 

[ninapee]

No worries about support we have a metal plate across the top of the gap....starting to worry about the lights now though

 

[flameport]

No worries about support we have a metal plate across the top of the gap

A thin metal plate
or
a substantial metal beam, the size of which was properly calculated and which required several people to lift into position?

 

[EFLImpudence]

No worries about support we have a metal plate across the top of the gap.

Would you like to reword that?
Is the gap now supporting the chimney and the metal plate?