H1 Energy Efficiency Update
All building work in New Zealand must comply with the Building Code to ensure safety, durability and efficiency for all users / occupants. As part of this, Section H1 of the Building Code sets out the energy efficiency requirements and Acceptable Solution (AS) / Verification Method (VM) assessment approach, depending on the size and use of the building.
In recent months some changes have been made to the requirements of H1 Energy Efficiency, which are now coming into mandatory effect. These include adjustment to the climate zones, building classifications and calculation / modelling methodology and also the R-values, all of which will affect the performance and efficiency of the building.
New Zealand has now been split into six climate zones, with associated R-value requirements aligned across windows, walls, roofs, floors, doors and skylights.
The updated requirements have provided five categories in which to assess a building as follows:
- AS1: Acceptable Solution H1/AS1 Energy efficiency for all housing, and buildings up to 300 m²;
- AS2: Acceptable Solution H1/AS2 Energy efficiency for buildings > 300 m²;
- VM1: Verification Method H1/VM1 Energy efficiency for all housing, and buildings up to 300 m²;
- VM2: Verification Method H1/VM2 Energy efficiency for buildings > 300 m²;
- VM3: Verification Method H1/VM3 Energy efficiency of HVAC systems in commercial buildings.
The choice of Acceptable Solution or Verification Method classification is dependent on the attributes of your building, i.e. area of glazing and location, R-values and wall / door area.
The external fabric of buildings has been reassessed, increasing performance requirements to reduce heat loss or solar gain and therefore improve the efficiency of HVAC systems, some notable changes include:
- Walls: wall R-Values now also apply to the doors located within them
- Floors: new minimum values for both slabs on ground and other floors types
- Window performance now considers the frame area, glass area and glass edge length. This will mean that larger windows are more affected by glass R-value and smaller winders are more affected by frame R-value.
For more detail, please refer to our Technical Note – H1 Energy Efficiency Requirement Updates October 2022.
Ensure you understand the changes and their impact on your construction projects. You may need to alter some internal processes or outsource some elements to ensure compliance with the new requirements of the Building Code.