SNZ NZS 4246
Energy efficiency – Installing bulk thermal insulation in residential buildings
|Publication Date:||30 August 2016|
This standard outlines methods of installing insulation products in common residential light-timber and steel-framed construction types. Information on the safe installation (clearances, health and safety) of insulating materials is appended.
The detail in the standard is based on residential-type construction, but the methods may be appropriate to other constructions.
The standard covers both the installing of insulation in new buildings during construction and the retrofitting of insulation in existing buildings.
On-ground vapour barriers have been included although they are not, in themselves, insulation products, because reducing the migration of water vapour into the subfloor space helps keep indoor air drier, reducing condensation and the growth of mould and mildew, which helps maintain a healthy living environment in buildings.
The following product types and applications are covered by this standard:
(a) Loose-fill product (such as wool, mineral wool, or cellulose fibre) for insulating walls and ceilings;
(b) Segment and blanket products (such as polyester, wool or mineral wool) for insulating walls, ceilings, and floors;
(c) Rigid sheet insulation products (such as expanded or extruded polystyrene (EPS or XPS) and polyisocyanurate (PIR) for insulating walls, ceilings, and floors;
(d) Semi-rigid insulation (such as wool, mineral wool, polyester) for insulating walls, ceilings, and floors;
(e) Pipe insulation (such as pre-formed tubular foam);
(f) Hot water cylinder wraps (such as wool, mineral wool, or polyester blanket with cloth or foil-backing);
(g) On-ground vapour barriers.
Thermal breaks for steel-framed constructions are referenced in this standard but not covered in detail.
Included in this standard is advice about the safe and effective installation of insulation around recessed luminaires. This information is limited to situations where the luminaires are already in place before the insulation is installed and therefore does not provide guidance to registered electricians when installing or replacing luminaires in ceilings that are already insulated.
This standard excludes installation of:
(a) Structural elements of buildings that provide inherent thermal resistance;
(b) Insulation in buildings with specific design, including freezers or cool stores;
(c) Insulation in buildings where insulation is part of the cladding material, such as exterior insulation and finish systems (EIFS);
(d) Insulation for purposes other than for thermal benefit, such as acoustic;
(e) Vapour barriers where these may be required in building elements around areas such as spa pools, swimming pools, or mountain lodges;
(f) Passive thermal design;
(g) Pre-assembled insulating systems;
(h) Double glazing (for further information on glazing and R-values, refer to NZS 4218);
(i) Expanding in situ foams;
(j) Radiant barriers in walls and ceilings;
(k) Foil insulation;
(l) Insulation in ventilation cavities of walls, including brick veneer cavities;
(m) Insulation in the cavity of double brick walls.