Ducted grease-extractor in ceiling instead of a cooker hood — silly idea?

[Dreadnaught]

I don't really like the look of cooker hoods, especially those above an island hob. Not to mention that they are expensive.

 

So I have been researching mounting an extractor grill in the ceiling above the hob instead.

 

Seems easy to do. Just mount an egg-crate grill with plenum containing a grease filter in to the ceiling. Run ducting through the web joists to the adjacent utility room and a second exhaust grill. Locate a variable speed fan in the utility room so it is quiet. Put a variable switch near the hob.

 

Flawed idea?

 

Edited December 2, 2019 by Dreadnaught

[Mr Punter]

The idea of the hood is to capture the smoke and steam before it escapes into the rest of the room.  Unless you have a very powerful fan and a large area grille I think it may disperse before it gets extracted.

 

I like stir-fry and cooking meat on a griddle, so I have a hood with grease filter but with a fan mounted remotely in a plant room above to make it quieter.  I used a variable speed controller but it seems fairly useless so I just switch to full.  I used 150mm duct and a Soler&Palau 200mm fan.

[Dreadnaught]

Thanks @Mr Punter. Helpful.

 

Good point about the hood. I am relying on the fact that the hot cooking-oil should rise up, rather like a mushroom cloud. I have a hunch it will be moderately effective even without a hood. You are quite right, it will need a fairly high flow rate to work well and some escape in the room will be inevitable. 

 

Good recommendation on the fan. Looks ideal!

 

As a grease filter, which did you use: fleece, metal or baffle? The baffle one's might look rather nice on show in my ceiling I think.

 

 

Edited December 2, 2019 by Dreadnaught

[vivienz]

Won't it make the ceiling around the vent greasy and icky?

[Dreadnaught]

@vivienz ah, hopefully not. Truth be told, I don't really cook an awful lot so I could probably get by without one at all. I am expecting that this arrangement will be superior to no hood at all and I wondering if it will actually prove surprisingly effective with a decent flow rate using the fan @Mr Punter suggested..

 

And, after all, I grew up in a house without a cooker hood at all without too many visible effects on the decor.

 

Hmm, perhaps I am deluded.

[vivienz]

I had in mind ceilings above cooker hoods and how these areas tend to get greasy and dirty. The extract draws the oil upwards but not all of it goes into the filter. It takes time to accumulate, though.

[Mr Punter]

I adapted a cooker hood - removed the motor but left the metal grease filters so they can be put in the dishwasher from time to time.

 

The larger the fan and ducting, the better.

[Conor]

Similar to what I'm planning, flush filter units mounted in a drop ceiling bulkhead, ducting to external wall and an external mounted fan unit for silent operation. Insulated damper to maintain air tightness when not in use.  Plan to have the ceiling surfaces within the bulkhead above the island made from MDF painted in wipeable kitchen paint... For those once a year cleans!

[Gone West]

14 hours ago, Dreadnaught said:

And, after all, I grew up in a house without a cooker hood at all without too many visible effects on the decor.

After we moved into my Mum's old bungalow, without a cooker hood, it took quite some time cleaning the oily film off the units near the hob. I never noticed it when visiting though.

[Dreadnaught]

Thank you all. Very helpful. You have certainly got me thinking about the right issues I think.

 

These thoughts have prompted me to rethink the hob's location. My previous idea was to have it against a wall but that is directly beneath a roof window above. I now realise that that roof window might be difficult to clean and may quickly become dirty.

 

Might therefore be better to move the hob to the island (with my vent in the flat ceiling above).

 

I also like the idea of using a wipe-clean gloss paint in the area around the vent itself. Good idea @Conor.

 

 

[Conor]

9 minutes ago, Dreadnaught said:

 

 

I also like the idea of using a wipe-clean gloss paint in the area around the vent itself. Good idea @Conor.

 

 

Dulux endurance kitchen paint. Have it behind our current hob instead of a splashback. Very easy to wipe down and surprisingly durable so far.

 

Edited December 3, 2019 by Conor

[Dreadnaught]

3 minutes ago, Conor said:

Dulux endurance kitchen paint

 

Good recommendation. Thanks. I see it comes in matt too and "Dulux Easycare Kitchen paint is an exceptionally tough grease resistant paint.":

 

The colour choice, however, looks a little bit primary but the may just be my screen:

 

[Dreadnaught]

Oh no, that was just a website tool. The colour palettes seems to be:

 

 

… much less Laurence Llewelyn-Bowen. 

[OwenF]

@Dreadnaught & @Conor sorry to resurrect an old thread but did you ever succeed with your ceiling mounted solution?

 

I’ve struggled to find ceiling mounted grills/plenums (without motor) that aren’t super expensive all-in-ones.

 

Found these which seem reasonably priced. But not sure how ‘pretty’ they look in domestic setting, nor how effective they are: https://www.justfans.co.uk/kitchen-extract-grille-with-grease-filter-450-150-cef-p-1454.html

 

Edited January 19 by OwenF

[Conor]

Went for downdraft hob. Far better.

[Dreadnaught]

@OwenF , ceiling mounted solution: no. I redesigned the kitchen and have moved the hob off the island, which makes an extractor much easier to design. I will be building it within the next 6-months.

 

If I had kept it on the island, I would have chosen a downdraft extractor, albeit I think they are flawed in terms of effectiveness given that hot gases rise and fast.

[Russdl]

Our down draft hob has a washable grease filter and a rechargeable charcoal filter. It expels the air at floor level below a standard ceiling mounted MVHR extract duct.
 

I didn’t expect it to be completely effective for the reasons @Dreadnaught mentions, but after two and a half years of use I’d have to say that it is. There is no evidence of grease etc in the MVHR extract duct and the pendant lights that hang down to about a meter above the back of the hob are equally unmarked. We don’t fry a great deal of food which will obviously help but I’d say the down draft hobs are more effective than you might expect. 

[Blooda]

14 minutes ago, Russdl said:

Our down draft hob has a washable grease filter and a rechargeable charcoal filter. It expels the air at floor level below a standard ceiling mounted MVHR extract duct.
 

I didn’t expect it to be completely effective for the reasons @Dreadnaught mentions, but after two and a half years of use I’d have to say that it is. There is no evidence of grease etc in the MVHR extract duct and the pendant lights that hang down to about a meter above the back of the hob are equally unmarked. We don’t fry a great deal of food which will obviously help but I’d say the down draft hobs are more effective than you might expect. 

 

Similar here, Elica Switch, downdraft hob, which I think is the same as @Conor from previous discussions.  With standard MVHR ceiling vent near by.  The filter and constant movement of air from the MVHR is sufficient for cooking, without boosting.

 

Ironically the only time we really use the MVHR Boost is when we clean the Charcoal filters, from the hob [once every three months or so] in the oven, as the make a rank smell.  

 

 

[Russdl]

@Blooda exactly the same! 
 

We only use boost when cleaning the charcoal filter. Did it a couple of days ago when the sun was shining bright. Absolutely poisonous. The instructions do say to make sure the room is well ventilated but it was way too cold to open a door/window 😂

[dpmiller]

@Russdl how are you "cleaning" the charcoal filter?

[Russdl]

@dpmiller it goes in a cold oven that is then heated to 200 degrees (iirc) for an hour and then left to cool down. The kitchen is a no go zone for a good couple of hours. Obviously not a problem in the summer when doors and windows are opened. 

[OwenF]

@Conor @Dreadnaught @Russdl thanks for feedback.

I don’t have MVHR (just poor mans variety PIV) so don’t think downdraft/ recirculating is for me.

 

I’ll keep looking at the industrial grille, plenum and remote tan solution.

 

Our hob will be on peninsular and have agonised over whether wall would be better for extract options. Ironically, the peninsula makes exhaust up through GF loft tile vent much simpler!