Extractor fans in new kitchens and building regulations
Anonymous user 23/02/2024 - 3.24 PM
Hi there, have a few questions about these as apparently as they are mandatory with new kitchen installs. What I'm reading is min extraction rate of 60 ltrs per minute, not situated too near a window. My cooker is planned to be on a wall I can't drill through - so can I put the extractor fan on a drillable wall adjacent, say about 2-2.5 metres away diagonally?
I can't really do a hood extractor due to low ceiling constraints.
Also - does it need to vent directly to the outside? There is a partially open void space on the other side of the kitchen wall, will I need to bridge that void gap with a length of ducting to reach the actual external wall?
This is purely to comply with building control - I don't cook much at all, and when I do I just pop a window tbh!
Are you a tradesperson and able to answer this question?
The possible option you have is to fit the duct in the ceiling void in between the floor/ceiling joists. The ducting can then be taken to, I'm guessing, the opposite external wall.
You may find some minor obstacles in the way such as herringbone struts or noggins, or even some pipes.but you should be able to get through using 100mm flexi hose or 100 x 50mm rectangular section. We have used this system on many occasions. Only minor expense is remaking the ceiling unless you can access from above but often a tiled floor of a bathroom is above the kitchen.
It would be ideal to have the cooker hood acting as the extraction element, so ducting to an outside wall would be the solution. If that is too difficult then a suitably powerful extract fan can be situated on an outside wall to satisfy building regs requirements. All extract fans must vent externally.
It’s always a good idea to ducted out if you can, but not all Extractor Installations can be fitted on an exterior wall due to the customers kitchen layout.
Theirs always the option of Charcoal filters, but to be honest no way as near as good as ducting all the greasy air out.
If a customer has no choice than to use a charcoal filter because of the layout, it’s always good to open a window to let the air circulate around the room.
Most Kitchen Appliance Manufacturers cover both optional and give you the choice to order the ducting kit or the filters.
My best option would be as follows, if the extractor is fixed to an internal wall and theirs no way of going though the wall or around the ceiling joists with a 100mm or 125mm ducting flex hose.
You can design your kitchen so you have a External wall to the left or right of the extractor. This means having a flyover shelve or bridging between the two unis either side of the cooker or hob.
You can use the flat box extractor system that comes with plenty of options to lay on top of the kitchen wall units, this gives you the choice to extract out though an external wall to the sides of your extractor, you would have to consider this when planing your kitchen at the early stages.
A hood extractor fan is roughly 600mm above the hob but follow the manufacturers instructions, so therefore the top of the extractor is generally quite low compared to the ceiling height, I would try & box in some ducting rather than disturbing the ceiling if possible to the nearest outside wall & vent it through, rectangular ducting is fairly slim & may work. Hard to picture without viewing the room.
