Technical specifications for pre-insulated foam duct
The duct to be made of pre-insulated FOM as Pure PIR panel
which resist propagation of fire and non poisonous gases,
minimum foam density should be (45kg/m3), foam ducts to be
covered with two layers of hard Aluminium with a minimum
thickness of 80 micron each, the total thickness of foam panel
The contractor will provide and install the ducts with all
accessories and installation materials
Duct sections to be assembled together by means of aluminium
flanges equipped with (P.V.C) hidden fastener. The flange
corners to be covered with (P.V.C) cover, and sealed silicon
rubber. The aluminium flange has to be clean and shut tight
without any leakage.
Large ducts which one of it’s dimensions is more than 1000
mm should be supported internally by round aluminium profiles.
Number of supports and their details to be according to foam
panel producer standard.
The contractor has to get management approval for
installation details. If there is any difference between the
duct’s aperture and dimensions on layout ,the modification will
be done according to the supervisor’s instructions.
Duct supporters to be as following:
One every four meters when duct size less than 1000x1200
One every two meters when duct size over than 1000x1200
Air ducts to be manufactured as following:
The reducer’s maximum angle should not exceed 30 °.
The elbows not be in sharp corners, the central line of
elbow should not be less than 1.5 time the width of the
duct, otherwise splitters to be installed inside the elbows
to direct the air.
The contractor is able to change the air duct’s dimension if
it’s necessary, keeping the same equivalent section area of it,
and this to be approved by the supervision engineer
The air duct to be produced, and installed according to (ASHRAE)
or (SMACNA) standards.
The straight duct will be
calculated in square meters, by measurement the outside
dimensions of each length of the executed duct.
The fittings (elbow, tee, and reducer) will be calculated in
square meters by measurement their outside areas.