Thread: range hood exhaust

you don't have to vent the rangehood to the outside but itis advisable.Some rangehoods have a charcoal filter for recirculating mode.But it is better to duct it to the outside to rid the house of smoke and cooking smells.It is usually 100mm,so you can use PVC,or buy a rangehood ducting kit from bunnings.Some people venmt them in to the roof space,but I think that defeats their purpose.Your cabinet maker should have provided a melamine dust or false back in the cupboard to conceal the duct.If he didn't,ask him for one.It shouldn't be a big deal.

Tools

Some rangehoods come with a fitting (optional extra) to convert them from vented to "recirculating" hoods. They're legal to use so it's fair to say that no, there's no legal requirement to vent 'em.

One thing to consider if you do vent; it's not just moisture going into the flue but a lot of fats'n'greases which deposit inside the flue and (if vented into the ceiling cavity) in the vicinity around the end of the vent. In a worst case scenario, the stuff ignites, I'd rather it was contained inside the flue where there's a good chance it'll just burn off, than have the fire spread into the ceiling cavity. :eek:

In other words... if ya vent, cover yer butt and install it properly. Plenty of clearance around the flue (don't bolt it along timbers!) and run it to the outsde. treat it like a chimney and you'll be right.

It is illegal to vent the rangehood into the roof cavity.

Bunnings sell a galvanised pipe duct kit with witches hat and lead flashing for about $105.00.

Do you have a slideout rangehood or a conventional rangehood?

Not sure on the type of rangehood, I dont think its a side out one. Will have to look at it and get back to you.

Thanks for letting me know about the legalities of the venting though

Originally Posted by untamed

Not sure on the type of rangehood, I dont think its a side out one. Will have to look at it and get back to you.

Thanks for letting me know about the legalities of the venting though

It must be a conventional rangehood then. It will suck up steam and then expel the air at the front (top) of the rangehood. Your doors (above the rangehood) will get very greasy and dirty over time. Make sure you keep cleaning the aluminium grease filters often. If the filters dont fit in your dishwasher then find a suitable container and fill with hot water and dishwashing powder. The caustic dishwashing powder will dissolve the cooking grease.

If you can remove the rangehood from the cabinet (couple of screws) you can then check to see if the rangehood can be vented from the rear through an external wall. This is a much easier way to vent the rangehood.

Originally Posted by renomart

It is illegal to vent the rangehood into the roof cavity.

Bunnings sell a galvanised pipe duct kit with witches hat and lead flashing for about $105.00.

Do you have a slideout rangehood or a conventional rangehood?

I work in the industry and have recently developed a new recirculation kit for slideout and built under rangehoods that have to be recirculated. Have a look at my website www.palmshore.com.au
Funny you should mention the illegal practice of venting the air from the rangehood into the roof or ceiling cavities. Its a very bad practice and habit by many builders.
Do you have a reference building code that I could check as different councils have different regulations and thank God there is now a national building code organisation that will make these codes standard accross Australia keeping everyone more safe.
My kits are purely internal.

Can you reference your comment about the illegality of venting into roof space? Poor practice, possibly (this is debatable) but illegal? References, please.

As with the previous advice, I would suggest venting to the outside to maximise your usage, though recirculating is an option, with carbon filters doing a moderate job of removing smells. If you have decent filters and clean them regularly you won't have a problem with grease coating flues and motors. That's what the grease filters are for (incidentally, though many say "dishwasher safe" most have aluminium frames which will eventually blacken in the dishwasher. To wash simply place in laundry tub, cover with hot water and add a drop of sugar soap.Next morning, rinse and refit).

Most rangehoods have a recirculating option, either front, front-top or through the flue outlet into the cavity behind your cupboard. Flues are usually 125mm or150mm and 1200mm lengths are around $20.

Good luck,

Mark

Originally Posted by silkwood

Can you reference your comment about the illegality of venting into roof space? Poor practice, possibly (this is debatable) but illegal? References, please.

Mmmmkay, my definition of 'legal' is 'one that is in accord with certain rules or laws.'

It may not be legal per se in Australian Statutory law....

But, in relation to Australian & New Zealand Kitchen Standards AS4386.2 I'd say that venting range hoods into the ceiling cavity is not in accord with their rules.

Local government / council regulations - ditto

Anyone know what the BCA rules say about this?

Legalities notwithstanding, "Best practices" are best practices. As Skew said, cover yer butt.

Joe

Another problem you can have is condensation build up in your roof. Not so bad if you are a flatlander in temperate climates but if you are living in snow country this will be a real issue.

What are the requirements for a slideout rangehood then? Please tell me it's easier than a conventional one, something has to be easy about installing a kitchen

They are both easy to duct. If your hood is place on an external wall you can simply 'punch through' the wall and duct it that way.

If your hood is placed on an internal wall you could simply go straight up and out through the roof or run the ducting along your wall cabinets to the external wall as previously stated.

Isn't installing a kitchen a barrel of laughs...

I have a recirculating rangehood on an internal wall and would like to have it ducted to the outside, but I don't want to do it myself. I don't have a clue who would do it, should I call an electrician or a plumber?

Ring a plumber - ask him/her if they duct hoods.

If they don't, ring another one.

The power sounds like it is already there, so nothing much should need to be done by a sparky except maybe rewiring a GPO.

Cheers,