35
5.2
HEBEL INSTALLATION
STEP 13: TRIPLE SKIN FLUE
Triple skin flue is to then be continued above the cavity lid. The
lower end of the triple skin casing shall be close fitting against
the lid and the outer casing must be ventilated. Air vents on
the first length of triple skin flue must be cut by the installer.
DUCTING:
CONNECTED TO
DESIGNATED
ROOM(S)
TRIPLE
SKIN
FLUE
ROOF CAVITY
1M
ABOVE
ROOF
LINE
STEP 14: FLUE INSTALLATION
The triple skin flue will then be continued into the roof cavity
and extended above the roof line as per AS/NZ 2918:2018.
There must be a 50mm clearance around the outer triple skin
flue. The flue must extend a minimum 1m above the roof line
and have a 3m diameter clearance from the top of the cowl to
any object in a horizontal direction.
**IMPORTANT**
Please note the flue should not include more than two 45°
bends. The angle of these bends cannot exceed more than 45°
and can have no more than one length of 900mm flue between
them.
STEP 15: VENTILATION
Using Hebel build a layer of bricks from the base to the top of
the ceiling on either side of the enclosure.
**IMPORTANT**
Ventilation is required on the enclosure to help with air
circulation. A minimum of two air intake grills are required
at the bottom and a minimum of two air out-take grills are
required on top of the masonry enclosure (2X inflow 2X
outflow). All vents can be positioned either side OR the front of
the masonry enclosure. ALL vents must adhere to the minimum
vent size of 600cm
2
.
Minimum vent sizes are 100mm x 300mm with a minimum
quantity of four*
*The vent sizes and quantity can be adapted and changed
BUT they must meet the minimum ventilation requirements
as specified above. For custom made vents please contact
your nearest dealer. ALL VENTS MUST NOT BE PLASTIC OR
COMBUSTIBLE.
*All air vents must have a minimum clearance to combustibles
of 600mm in front and 500mm above the metal vent itself.
