Sourcing and using rectangular ducting for kitchen extractor

queenmeabh

Hi all

Hoping someone can help.. Currently renovating a house and relocating the kitchen. We've bought a decent chimney extractor hood (Elica Galaxy) which requires a 150mm diameter duct. As it turns out, we don't have enough space to fit a duct of that diameter above the kitchen wall cabinets in our design. Our choices as we see it are:

(a) lower the height of the wall cabinets, OR
(b) source rectangular ducting of the same capacity that will fit in the space available.

Option (a) won't look great as the wall cabinets adjoin some high cabinets, so we really want to investigate (b).

So, can anyone:
- suggest places in Dublin where we could source rectangular ducting in a range of sizes, and whatever converters or adaptors are required?
- provide any advice on doing this, based on their own experience?

Thanks a million

DublinDilbert

queenmeabh wrote: »

Hi all

Hoping someone can help.. Currently renovating a house and relocating the kitchen. We've bought a decent chimney extractor hood (Elica Galaxy) which requires a 150mm diameter duct. As it turns out, we don't have enough space to fit a duct of that diameter above the kitchen wall cabinets in our design. Our choices as we see it are:

(a) lower the height of the wall cabinets, OR
(b) source rectangular ducting of the same capacity that will fit in the space available.

Option (a) won't look great as the wall cabinets adjoin some high cabinets, so we really want to investigate (b).

So, can anyone:
- suggest places in Dublin where we could source rectangular ducting in a range of sizes, and whatever converters or adaptors are required?
- provide any advice on doing this, based on their own experience?

Thanks a million

You won't get a rectangular duct with the same cross section easily. You will get rectangular rigid ducting and fittings to bring to a 4" duct. Woodies stock it and goodwins.ie .

How long is the run? I've used rectangular ducting a few times with no issue. Manufacturers always say a 6" duct but for a short run you'll get away with smalller.

queenmeabh

DublinDilbert wrote: »

You won't get a rectangular duct with the same cross section easily. You will get rectangular rigid ducting and fittings to bring to a 4" duct. Woodies stock it and goodwins.ie .

How long is the run? I've used rectangular ducting a few times with no issue. Manufacturers always say a 6" duct but for a short run you'll get away with smalller.

Hi there

Thanks for the quick reply! The run is about 1200mm - not long. But I've had so many bad experiences of extractors that I want to make sure that the ducting matches my (not particularly cheap) hood, so the advice had been to go for 6 inches if it all possible.

Calahonda52

queenmeabh wrote: »

Hi there

Thanks for the quick reply! The run is about 1200mm - not long. But I've had so many bad experiences of extractors that I want to make sure that the ducting matches my (not particularly cheap) hood, so the advice had been to go for 6 inches if it all possible.

run length alone is not enough info, how many bends is key as this is where the pressure loss occurs
http://www.pressure-drop.com/Online-Calculator/

Am a bit puzzled here:

Normal ceiling 2400mm
duct 150 is too big => top of presses are above 2250?

the_pen_turner

how about using 2 4" rectangular ones.

how about getting one made up from stainless steel and powdercoating it

queenmeabh

Calahonda52 wrote: »

run length alone is not enough info, how many bends is key as this is where the pressure loss occurs
http://www.pressure-drop.com/Online-Calculator/

Am a bit puzzled here:

Normal ceiling 2400mm
duct 150 is too big => top of presses are above 2250?

Hi there

Thanks for that. It's a straight run which should make things better.

The top of the presses will be about 2280 (using tall units with 80mm feet) and once floor tiling and ceiling slabs are taken into account, there won't be enough space...

queenmeabh

the_pen_turner wrote: »

how about using 2 4" rectangular ones.

how about getting one made up from stainless steel and powdercoating it

Hi there

Thanks for that. Since I wrote the original post, we've been looking online and have found a company in Munster that supply 90x220cm rectangular ducts and round-to-rectangular converters, so we're hoping that might do the job...

the_pen_turner

queenmeabh wrote: »

Hi there

Thanks for that. Since I wrote the original post, we've been looking online and have found a company in Munster that supply 90x220cm rectangular ducts and round-to-rectangular converters, so we're hoping that might do the job...

can you pm where you scourced it please.