Cooker Hood - extraction via duct or ductless?

[spiidey]

We have the following cooker hood:-

http://www.currys.co.uk/gbuk/built-...UbtPcQAABe1p@1De:20130826163239:s#prd17316295

We've had acoustic insulation put in the cavity between the kitchen ceiling and the bedroom floor above. We're sensitive to noise and have therefore had the full cavity installed with acoustic insulation, which meant that the venting pipe that took the air from the cooker hood to the outside has now been realigned. However, whilst it has been realigned, the end of the venting pipe that would have attached to an outside wall is now just sitting loose underneath another of the upstairs bedrooms.

The chap who carried out the soundproofing works has suggested that we just replace the filters in the hood with carbon filters and we'll be able to run it as normal, and that there won't be any problems with either (a) the hood (e.g. burning out), or (b) a build up of moisture/air underneath the other upstairs bedroom (where the end of the venting pipe is effectively just sitting loose).

Is this correct? Or do we need to remove this cooker hood and get a ductless hood installed?

 

[JohnD]

a cooker hood has got to extract through a wall and outside the dwelling. Otherwise it is nothing but a kitchen ornament.

the idea of letting the exhaust hose vent into a void is ludicrous. It will become damp and smelly.

You can run the duct under the ceiling and above the wall cabinets. It will probably be out of sight but you can if you wish use rectangular ducting rather than round and you cabn if you wish paint it to match the wall. After a day or two you will not see it.

If the wall cabinets go right up to the ceiling you can run the duct inside the top cabs.

 

[spiidey]

a cooker hood has got to extract through a wall and outside the dwelling. Otherwise it is nothing but a kitchen ornament.

the idea of letting the exhaust hose vent into a void is ludicrous. It will become damp and smelly.

You can run the duct under the ceiling and above the wall cabinets. It will probably be out of sight but you can if you wish use rectangular ducting rather than round and you can if you wish paint it to match the wall. After a day or two you will not see it.

If the wall cabinets go right up to the ceiling you can run the duct inside the top cabs.

Hi John

Thanks for the reply - exactly as I thought.

So using carbon filters would help but there would still be moisture/grease going up through the venting pipe and into the void?

What about hoods that recirculate air only? Such as this one:-

http://www.currys.co.uk/gbuk/built-...cooker-hood-stainless-steel-18244003-pdt.html

If we were to go down the route of running the duct underneath the kitchen ceiling (and above the wall cabinets), would we need to lower the height of the hood so that the venting pipe was able to come vertically out of the top of the hood as normal and then bend 90 degrees to run horizontally alongside the ceiling?

Do you have a link for rectangular ducting?

 

[JohnD]

A recirculating hood is useless.

cooker hoods are usually made so they can vent from back or sides, to suit various kitchens. Yours appears to be a chimney type. Probably the top chimney can be adjusted in height, if all else fails a hole could be cut in the side. It is probably very thin sheet steel which can be cut with a sturdy pair of scissors, or you could use a nibbler or jigsaw, or even a small hacksaw.

http://www.screwfix.com/c/ventilation/ducting/cat840506

 

[john316xx]

JohnD

I came across one of your posts that was really helpful, so I joined this forum to get in touch with you to perhaps discuss your thoughts further.

However, I cant see how to contact you so hopefully you will see this post and make that contact.

zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

THANKS

John

 

[HERTS P&D]

 

[spiidey]

Ok, so our chap is back out and has proposed the following 2 options:-


1. Run a duct from the chimney horizontally below the ceiling, and above the wall cabinets, venting to an outside wall. Cost £300

2. Repoint the chimney so that it vents direct to the partition directly behind the hood, install carbon filters in the hood, and install a grille/vent in the partition to allow any non-filtered air that goes into the partition to disperse. Cost £zero


Our preference would be for Option 1, but if we can minimise cost and go for Option 2 without any short, medium or long-term problems, then clearly that would be the better option.

Thoughts?

 

[JohnD]

option 2 is 100% useless. Also, blowing steamy, smelly, greasy air into a void is a terrible idea. Is he an idiot?

Go for option 1

 

[spiidey]

option 2 is 100% useless. Also, blowing steamy, smelly, greasy air into a void is a terrible idea. Is he an idiot?

Go for option 1

John

Thanks again for the reply.

Is Option 2 100% useless even with carbon filters placed in the hood?

 

[JohnD]

yes

all the steam will pass through, and half the smell.

 

[gsportgeorge]

Can you vent up the chimney if it is out of use?

 

[spiidey]

Workman has proposed a new solution - run a duct from extractor hood and into eves above garage.

He proposes that this will work as the duct will extract to an area with a cross-wind.

The eves of the garage have soffits either side so this appears to make sense.

Thoughts?

 

[JohnD]

how will you prevent food smells blowing back through the eaves?

 

[spiidey]

how will you prevent food smells blowing back through the eaves?

Eves above garage are only above garage - soffit runs from front of garage to back of garage.

 

[OwainDIYer]

Workman has proposed a new solution - run a duct from extractor hood and into eves above garage.

He proposes that this will work as the duct will extract to an area with a cross-wind.

The eves of the garage have soffits either side so this appears to make sense.

Thoughts?

Extractor fans have to vent to the outside air. Not to building cavities, voids, attics, etc.

There is no other solution.

If you don't want to spend £300 doing the job properly don't buy the hood at all and just open the window.