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Big changes are included for energy efficiency in NCC 2022 – do you know what this means for Performance Solutions?

NCC 2022 includes several changes to energy efficiency Performance Requirements and Verification Methods.

In this article, we summarise some of these new and updated performance provisions.

Energy Efficiency Performance Requirements

NCC Volume Two

Volume Two has 2 new Performance Requirements:

  • H6P1 Thermal performance
  • H6P2 Energy usage.

H6P1, which replaces P2.6.1 of NCC 2019, provides quantified metrics for heating, cooling and total thermal energy loads and is applicable to habitable rooms and conditioned spaces.

The metrics for these energy loads are in a new specification in Section H of Volume Two (Specification 44).

H6P2, which replaces P2.6.1 of NCC 2019, provides quantified energy value upper limits for a building’s domestic services.

It introduces a new defined term for energy value, which is:

Energy Value: The net cost to society, including, but not limited to, costs to the building user, the environment and energy networks.

The energy value is the economic cost (or saving) from on-site energy usage or generation.

It differentially weights the impacts of fuel types used for domestic services primarily based on energy prices, impacts of pollution and impacts on energy networks.

The defined term ‘domestic services’, is expanded to include on-site renewable energy equipment.

NCC Volume One

Section J contains 3 new Performance Requirements:

  • J1P2 Thermal performance of a sole-occupancy unit (SOU) of a Class 2 building or a Class 4 part of a building.
  • J1P3 Energy usage of an SOU of a Class 2 building or a Class 4 part of a building.
  • J1P4 Renewable energy and electric vehicle charging.

J1P2 and J1P3 replicate H6P1 and H6P2 (Volume Two), whilst J1P4 requires buildings to have allowance for the installation of future renewable energy and electric vehicle charging infrastructure.

Note that J1P1 (2019: JP1) no longer applies to Class 2 SOUs or Class 4 parts of a building, as these are now addressed by J1P2 and J1P3.

Verification Methods

NCC Volume Two

H6V2 “Verification using a reference building” (2019: V2.6.2.2) includes additional modelling details to assist practitioners in the use of the Verification Method.

H6V3 “Verification of building envelope sealing” (2019: V2.6.2.3) also has additional requirements for ventilation, where a building’s air permeability is below 5 m3/hr.m2.

NCC Volume One

There are several changes to the Verification Methods in Section J of NCC Volume One.

  • J1V1 (2019: JV1) is expanded to include additional building classifications:
    • Class 2 buildings other than SOUs.
    • Class 3 buildings.
    • Class 6 shopping centres.
  • J1V4 (2019: JV4) includes additional ventilation requirements when the air permeability rate is below 5 m3/hr.m2 for a Class 2 SOU or a Class 4 part of a building.
  • J1V5 is a new reference building Verification Method for Class 2 SOUs. It is based off J1V3 (2019: JV3), but modified for the new Class 2 SOU requirements. Specification 45 provides modelling profiles when using J1V5.

What does this mean for developing Performance Solutions?

These changes provide users with more freedom to develop innovative building designs to meet the NCC Performance Requirements. They set clear targets for use in Performance Solutions. 

The new Verification Methods ensure more building classifications have equal access to this Assessment Method. Again, providing users with more freedom to develop compliant buildings with innovation in mind.