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7.2.158.6.3 Insulation to services
Insulation to internal services shall be in accordance with relevant Building Regulations and installed to minimise the effects of freezing, overheating or energy wastage. Issues to be taken into account include:
- space heating and hot water
- intermediate floors
- systems without hot water storage
- systems using hot water storage.
8.6.3.1 Space heating and hot water
Pipework serving space heating and hot water systems should be insulated in all areas outside of the heated building envelope. In addition, pipes should be insulated under the following conditions:
- all primary flow and return pipework from the heat source to hot water storage cylinder including where they pass through an intermediate floor void
- any pipework, flow and return, hot or cold distribution or feed pipe within 1m minimum of the cylinder
- any secondary return circuits
- meet the minimum pipe insulation requirements of Clause 8.6.4.
8.6.3.2 Intermediate floors
Where pipework is installed within intermediate floors, it should be insulated over the complete length.
When installing pipes through timber joists, to prevent excessive hole diameters, the insulation should only be applied between each joist; the pipes should be wrapped where they pass through the joist so they can move freely and without noise.
The following pipework should be insulated:
- pipework within a garage (outside the heated living space)
- pipework that passes through a roof space (outside the heated living space)
- pipework that passes through an external wall cavity, that is on the cold side of the external wall insulation (outside the heated living space).
Pipework should be insulated to meet the minimum requirements in Clause 8.6.4.
Figure 5: Insulation to space heating systems without storage
Figure 6: Loft area
Figure 7: Garage and void area
8.6.3.4 Systems using hot water storage
The following pipework should be insulated:
- pipework within a garage (outside the heated living space)
- pipework that passes through a roof space (outside the heated living space)
- pipework that passes through an external wall void that is on the cold side of the external wall insulation (outside the heated living space)
- all hot water primary flow and return pipework including where they pass through an intermediate floor (void)
- pipework within 1m of the hot water storage cylinder.
If secondary circulation is used, insulate all pipework that is kept hot by that circulation.
Pipe insulation and hot water cylinders should be insulated to meet minimum requirements in Clause 8.6.4.
Figure 8: Insulation to space heating systems with storage
Figure 9: Loft area
Figure 10: Garage and void area
Figure 11: Airing cupboard
Last updated: 2nd January 2025