hob extractor ducting or not

[cheradenine]

Planning ahead for a kitchen central island, with in an ideal world extracting either into the disused chimney flue, or to the side wall.

Of course, the joists go the wrong way for that.

They are relatively large however - 8" at 12-14" centres, for a ~3m span. The whole ceiling will be down for renovation. One thought is that flat ducting through the middle of the joists might work, with some suitable bracing (maybe steel plates bolted through).

An alternative thought is to abandon in favour of a recirculating unvented fan like our old house (aka a 'fat accelerator')..

thoughts?

 

[Ian H]

Lower the ceiling by 100mm?

 

[cheradenine]

Yeah.. problem is though that section of the kitchen is only a 3m span (going into a steel), it's just one bit of a much bigger room (kitchen/dining room knock-through) :-/