# Forum Home Renovation Kitchens  Rangehood with roof top Flue

## mirz

I am in middle of DIY 600mm Canopy type rangehood, and going to install Flue to push all the smoke and food smell out of the house.  Its a tiled roof, and I bought a flashing sheet from Bunnings, which is bit double the size of normal tile.<O :Tongue: </O :Tongue:  <O :Tongue: </O :Tongue:   · How high the Clow should go from the tiles? 200, 500, or 1000mm?<O :Tongue: </O :Tongue:  · What sort of tool should I use to make a hole in middle of flashing to pass through 150mm pipe through it?<O :Tongue: </O :Tongue:  · There is no stud in wall behind the rangehood, so should I use those 20kg Heavy (special spiral type of screws) to hold it on plaster board? Would that be enough to hold its weight or any other suggestion?<O :Tongue: </O :Tongue:

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## arms

> I am in middle of DIY 600mm Canopy type rangehood, and going to install Flue to push all the smoke and food smell out of the house.  Its a tiled roof, and I bought a flashing sheet from Bunnings, which is bit double the size of normal tile.<O</O <O</O  · How high the Clow should go from the tiles? 200, 500, or 1000mm?<O</O · What sort of tool should I use to make a hole in middle of flashing to pass through 150mm pipe through it?<O</O · There is no stud in wall behind the rangehood, so should I use those 20kg Heavy (special spiral type of screws) to hold it on plaster board? Would that be enough to hold its weight or any other suggestion?<O</O

  surely these questions would have been asked at bunnings before you bought the flue  :Doh:

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## Make it work

By those spiral screws are you refering to the screw in gypsum anchor such as the Buildex Wallmate or the Powers Zip it? 
They will work but obviously can only hold as much weight as the plasterboard will support. The trick here is to use every mounting hole in the range hood so if there are only 4 use all 4 but if there are 10, use all 10. 
They will work better in gyprock than in fibrous plaster and the metal ones are better than plastic because the self tapping screw has less tendancy to strip out. 
I have used both these types and I prefer the Powers Zip it because it tends to go in tighter and stay on centre when used correctly, theh also pull in to be completely flush with the surface of the board so you don't have any proud anchors to unsettle the thing you are mounting. 
My suggestion is have a few practice goes in a piece of scrap plaster board (you can reuse the metal ones a number if times) then mark the centres and set the anchors in the wall.

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## mirz

> surely these questions would have been asked at bunnings before you bought the flue

  As there were no person available in plumbing area, could not ask these questions at that time. :Rolleyes:  
my rangehood came with 2.1m flexi pipe, so thats why i only bought Clow and Flashing from Bunnings.  :Smilie:  
but when i looked at roof other Clows ( on neighbours houses) are raised by about 1m from tile's level, any reason why need to raise it to 1m? 
I tried using 3 out of 3 metal scrwes (to hold 20Kg) to attatch rangehood to wall, and its looking pretty stready at the moment. but i am bit concerned if over the time wall's plaster will loose its strength and it will fall over  :Confused:  
(dont remember brand name, but will check tonight at home and write back here)

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## mirz

finally i have installed rangehood, and passed its flue to roof (inside area). next thing is to take flue out through a tile and connect cowl to it. 
any suggestion how/which tool should i use to make a hole through lead flashing? thanks.  
what i have done today:
made a hole in plaster board wall about 200 x 100 mm, just above where spiral screws are, took the whole piece out.
place a solid wood (450x60x20 ) right behind spiral screw, and replaced spiral screws with long wooden screws.
placed my cutout back in place and did a small polyfila job.
whole cutout is now right behind SS decorative rectangle.
now looking rock solid  :Smilie:  
btw spiral screws are made by wallmate.

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## rrobor

Thats a lot of work for very little, your roof if tiled is liable to be very well vented, a rangehood traps most if not all the grease etc in filters so its only air going up. My rangehood flue has been in place for 25 years with the flue venting in the roofspace against a roof bearer, there is no sign on that bearer of any contamination from cooking.

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## mirz

here is a picture how it looks now  :Biggrin:

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## arms

any suggestion how/which tool should i use to make a hole through lead flashing? thanks. 
 there are special lead flashings premade for this application ,just bashing through lead wont create a suitable seal ,go to a good plumbing outlet (not a hardware store) and tell them what you require ,also chimneys/flues are set to have the outlet above the uppermost pitch of the roof to allow the wind to draw fumes away from the roof and house

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## mirz

thanks for your advise Tom, will checkout local plumbtec tomorrow to find out what have to offer.

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