The piping insulation on internal and external piping must also be entered into BASIX. The insulation level influences the amount of heat lost from the hot water and therefore the energy use of the hot water system. The insulation options are:
- No external/internal pipework
- R1.0 (~38 mm)
- R0.75 (~32 mm)
- R0.6 (~25 mm)
- R0.45 (~20 mm)
- R0.3 (13 mm)
Piping insulation (ringmain and supply riser)
The National Construction Code specifies minimum piping insulation requirements for central hot water system pipes.
Insulation can be made from a closed cell polymer, nitrile, fibreglass or equivalent.
Insulation is applied to the central hot water system's ringmain and supply risers. Note that pipe connections should also be insulated.
For more detailed information on hot water system piping materials and thicknesses (R-values) contact your local piping insulation manufacturer.
Pipe sizing
Hot water pipe diameter and length is not currently assessed in BASIX, since design of these occurs after approval of the development application for the proposed development. It is still important to recognise their importance to good design.
Design the centralised hot water system at the early planning stages of a development to ensure adequate space within the building to position centralised hot water piping, its associated insulation and storage tanks.
Carry out the design of a central hot water system through a qualified hydraulic consultant briefed to aim for best practice.