Page 102 - SMM2 eBOOK

Ductwork

Q14 Ducting and fittings

1. Ducting (measured over all ducting fittings, short running lengths and branches) shall be
given in metres stating the type and size. Joints in the running length shall be given in the
description stating the method of jointing. Stiffeners shall be given in the description.

2. Lining ducting internally with acoustic or protective material shall be measured separately
in metres stating the type and thickness of the lining material and the internal size of the
ducting.

3. Flexible ducting and extensible ducting (measured as fully extended) shall be described
and enumerated.

4. Curved ducting shall be so described and enumerated stating the mean radius. Curved
rectangular ducting shall state whether shaped to curve on the wider or narrower side.

5. Ducting fittings shall be described and enumerated as extra over the duct in which they
occur. Cutting and forming openings and jointing ducting to fittings shall be deemed to be
included. Fittings involving a change of direction of the ducting shall be described.

6. Providing materials, heat, bolts, nuts, washers and everything else necessary for making
joints in ducting shall be deemed to be included with the items.

Q.15 Special connections, etc.

1. Special connections and special joints in ducting shall each be enumerated separately
(except where given in the description of another enumerated item) stating the size and
kind of ducting concerned and the method of jointing. Classification shall be as follows:

a. Connections between ducting of differing materials.
b. Connections between ducting and equipment stating the nature of the equipment.
c Isolated joints which differ from those given in the description of the ducting.
d. Flexible connections between ducting and plant.

2. Ducting turns and splitters shall each be enumerated separately stating the type and
internal size of the ducting.

3. Noule outlets, test holes and covers and access doors shall each be described and
enumerated stating the size, the method of jointing and material and thickness or gauge of
the ducting and lining. The forming and stiffening of openings shall be deemed to be
included.

4. Cowls, terminals, intake louvres and the like shall each be enumerated stating the size
and type, the size of ducting to which it is attached and the method of jointing.

5. Weathering-aprons, flashing plates and the like where not forming an integral part of the
unit shall each be enumerated stating the type and size and the method of jointing.

Q.16 Ductwork supports

1. Components for supporting ductwork shall each be enumerated stating the size and type
of the component and the size of the ducting. Spring-compensated components shall be
so described stating the loading and the movement to be accommodated. Classification
shall be as follows:

a. Components for supporting single runs of ducting.

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