8.6.4 Insulation performance
Insulation performance shall comply with national standards. Issues to be taken into account include:
- thermal conductivity and pipe insulation size
- maximum daily hot water loss for hot water storage systems.
8.6.4.1 Thermal conductivity and pipe insulation size#
Minimum thickness of pipework insulation for hot water services and space heating applications using high performance insulation see table 2 below:
- all insulation used should be designed so that the permissible heat losses in BS 5422 for hot water services at 60°C are not exceeded for the different pipe sizes
- this table relates to both plastic and metal pipes.
Table 2: Pipe insulation thickness for high emissivity outer surface ε = 0.90)
Notes
For low emissivity see BS 5442 table 19A and 19B.
8.6.4.2 Maximum daily hot water loss for hot water storage systems#
Maximum daily heat loss for hot water storage cylinder should comply with table 3 below.
Table 3: Hot water storage heat loss
| Nominal Volume (litres) | Heat loss kWh/24h |
|---|---|
| 50 | 1.03 |
| 100 | 1.49 |
| 150 | 1.88 |
| 200 | 2.06 |
| 250 | 2.22 |
| 300 | 2.36 |
| 350 | 2.48 |
| 400 | 2.59 |
| 500 | 2.80 |
Last updated: 8th February 2024