Kitchen extractor installation - will this plan work?

[Reejoc]

I've just found out that our cooker hood is only recirculating and there is no ducting to the outside world. We're getting a lot of condensation on the walls and mold so this situation obviously needs addressing.

There's actually no possibility of getting ducting from a cooker hood in it's current position to the outside due to cupboards, soil pipe and no access to the ceiling directly above the cooker.

The ceiling above is plasterboard with ~30cm joist spacing. As far as I can tell the only option therefore would be to install an powerful 150mm inline extractor fan with a ceiling vent, about 50cm away from the cooker where I would be able to access the floorboards above. This could then extract to the outside world via a run of ~1m of rigid ducting between the joists.

I would use this sort of fan:

http://www.extractorfanworld.co.uk/...-inline-centrifugal-fan-with-timer-2788-p.asp

It claims 500m3/min which isn't far off a cooker hood. The kitchen is approx 16m3.

and this sort of grille:

http://www.ebay.co.uk/itm/Air-Vent-...-4-5-6-8-/151111303321?_trksid=p2054897.l4275
or
http://www.ebay.co.uk/itm/150mm-cei...oom-vent-/251399405633?_trksid=p2054897.l4275

Any thoughts on this? Would such a setup comply with building regulations?

Many thanks

 

[PrenticeBoyofDerry]

How would you gain access to the fan/impeller, for maintenance, inspection and testing?

 

[ericmark]

Will sound daft but two ways to stop moisture one is to extract moisture which also means allowing some way for that air to be replaced so double ducting one in and one out if your going to avoid drafts.

The other is don't make the moisture using induction hob instead of gas will vastly reduce the moisture produced both because your not burning gas and two because of the automation where it auto boils then simmers.

My house and my father-in-laws are identical he uses gas and I use induction his house is around the 65% humidity mine is around 40% humidity and two living in my house and only one in his.

I tease him that it's because he lives nearer to Mold our county town then me to which he points out different spelling.

Having something which forces an air exchange will reduce mould be it an extractor or tumble drier or even open window but sit in my living room and you know when tumble drier is running as there is a draft under front door opening my velox window does stop the draft if not raining.

Remember if you have any open flues then using an extractor can draw fumes into the house.

 

[Reejoc]

How would you gain access to the fan/impeller, for maintenance, inspection and testing?

Bare floorboards in bedroom above which are screwed down for easy access. I'd also probably have it covered in rockwool to keep the noise down in the room above.

Will sound daft but two ways to stop moisture one is to extract moisture which also means allowing some way for that air to be replaced so double ducting one in and one out if your going to avoid drafts.

The house has a positive pressure ventilation unit already fitted and is not exactly air tight either. I like the idea of an induction hob but we have a gas range cooker and replacing it isn't an option.