heated water piping encased in a concrete floor slab (except that which is part of a floor heating system), must in all climate zones, have a minimum material R-Value of 0.4.
(3) All piping located outside a building, or within a ventilated wall space, subfloor or roof space must have a minimum material R-Value of 0.6.
use thermal insulation material in accordance with AS/NZS 4859.1; and
be sealed against air loss—
by closing all openings in the surface, joints and seams of ductwork with adhesives, mastics, sealants or gaskets in accordance with AS 4254 for a Class C seal; or
for flexible ductwork, with a draw band in conjunction with a sealant or adhesive tape.
(2) Duct insulation located under a suspended floor, in an attached Class 10a building and in a roof space must—
be protected by an outer sleeve of protective sheeting to prevent the insulation becoming damp; and
have the outer protective sleeve sealed with adhesive tape not less than 48 mm wide creating an airtight and waterproof seal.
(3) The requirements of (1) do not apply to heating and cooling ductwork and fittings located within the insulated building envelope including a service riser within the conditioned space, internal floors between storeys and the like.
Insert NT table (13.7.4) 13.7.4 as follows:
NT Table 13.7.4: Heating and cooling ductwork and fittings – minimum total R-Value
NT 13.7.5 Water heater in a heated water supply systemNew for 2022
A water heater in a heated water supply system must be designed and installed in accordance with Part B2 of NCC Volume Three – Plumbing Code of Australia.