Delete clause 13.2.3 and insert NSW 13.2.3 as follows:
(1) A roof that—
has metal sheet roofing directly fixed to metal purlins, metal rafters or metal battens; and
does not have a ceiling lining or has a ceiling lining fixed directly to those metal purlins, metal rafters or metal battens,
must have a thermal break, consisting of a material with an R-Value of greater than or equal to 0.2, installed between the metal sheet roofing and its supporting metal purlins, metal rafters or metal battens.
(2) (1) does not apply to roofs constructed using insulated sandwich panels.
NSW 13.2.4 Roof lights
This clause been deliberately left blank
13.2.4 does not apply in NSW.
NSW 13.2.5 External walls2019: NSW 3.12.1.1
Delete clause 13.2.5 and insert NSW 13.2.5 as follows:
(1) A metal-framed wall that forms part of the building envelope must have a thermal break, consisting of a material with an R-Value of not less than R0.2, installed at all points of contact between the external cladding and the metal frame if the wall—
does not have a wall lining or has a wall lining that is fixed directly to the metal frame; and
is clad with weatherboards, fibre-cement or the like, or metal sheeting fixed to the metal frame.
(2) The requirements of (1) do not apply to walls constructed using insulated sandwich panels.
Explanatory information
A lightweight wall has no high thermal mass cladding on the outside or lining on the inside. Typically, this would represent a framed wall, clad externally with timber weatherboards, fibre-cement sheet, metal or autoclaved aerated concrete.
Because of the high thermal conductance of metal, a thermal break is needed when a metal framing member directly connects the external cladding to the internal lining or the internal environment. For the purposes of NSW 13.2.5(1)(b), expanded polystyrene strips greater than or equal to 12 mm thickness and timber greater than or equal to 20 mm thickness are deemed to achieve an R-Value greater than or equal to 0.2.
Many reflective insulation products that use perforations to increase their vapour permeance are not suitable for use behind vertical or diagonally orientated timber cladding boards, where required by clause 7.5.2 of the ABCB Housing Provisions, or behind open jointed or unsealed cladding systems.
NSW 13.2.6 Floors and subfloor walls2019: NSW 3.12.1.1
Delete clause 13.2.6 and insert NSW 13.2.6 as follows:
(1) A concrete slab-on-ground with an in-slab or in-screed heating or cooling system, must have insulation with an R-Value greater than or equal to 1.0, installed around the vertical edge of its perimeter.
be continuous from the adjacent finished ground level—
to a depth of greater than or equal to 300 mm; or
for at least the full depth of the vertical edge of the concrete slab-on-ground (see Figure 13.2.6).
(3) The requirements of (1) do not apply to an in-screed heating or cooling system used solely in a bathroom, amenity area or the like.
Explanatory information
NSW 13.2.6(3) provides an exemption for an in-screed heating or cooling system used solely in bathrooms, amenity areas and the like, as these are typically small areas.
Care should be taken to ensure that the type of termite management system selected is compatible with the slab edge insulation.