All over H1
Energy Efficiency (H1)
Want to be ‘All over H1’? Clause H1 of the New Zealand Building Code, which regulates the energy efficiency of buildings, is undergoing its biggest changes in more than a decade. The first phase of implementation began on Thursday 3 November 2022, with a further set of requirements beginning from 1 May 2023.
PlaceMakers is committed to providing you with the information you need to work within the rules. Currently the information provided here follows that provided by MBIE. Shortly, ‘All Over H1’ will also include detailed supplier solutions and related products, which will assist speed up the design process for most standard construction methods.
The update to Clause H1 aims to help make new buildings warmer, drier and healthier and therefore reduce the energy and environmental impact needed to heat them. The changes are the biggest energy efficiency updates to the acceptable solutions and verification methods in more than a decade.
The H1 Clause of the Building Code regulates the energy efficiency of the built environment – covering wall, floor and ceiling insulation, as well as the thermal performance of windows and doors. There are major increases in thermal performance requirements across the building envelope, indicated through higher construction R-values for different building elements.
Construction R-values in H1
An R-value is the measure used to describe the ability of a material or system to resist the transfer of heat. The higher the R-value, the better the thermal resistance.
There are two types of R-values commonly used in the construction industry:
1. Material R-values
The thermal performance of individual products eg, insulation.
2. Construction R-value
The total thermal performance (R-value) of a typical area of a building element. For a wall this would be derived from the R-values of the cladding, insulation material and a ‘typical area’ of wall framing.
The Building Code clause H1 documents specify construction R-values, not the R-value of the insulation product to be installed.
This is an important difference. For example, an R5.0 thermal ceiling insulation blanket may be used but the construction value of the ceiling may only be R4.0 once the total ceiling construction design is accounted for.
Two sets of requirements, three transition dates
Minimum insulation requirements differ across three types of buildings:
Small buildings – under 300m2.
Large buildings – over 300m2.
Housing covers all types of residential housing of any size including standalone houses, townhouses, and apartments. All other buildings are defined by size; small buildings under 300m2, and large buildings over 300m2.
The new housing and small building insulation requirements are the same. The only difference between them is the transition date for the new final values to come into effect, as outlined below.
Large building requirements differ from housing and small building requirements.
Industrial, assembly service and ancillary buildings, as well as outbuildings, currently sit outside the scope of this work. However, where there is an office within a warehouse or industrial building that office would have to comply with the new requirements.
New climate zones
Previously, New Zealand was divided into three climate zones – Zones 1 and 2 for most of the North Island and Zone 3 for the South Island and the central plateau. There are now six climate zones across New Zealand, and the new insulation requirements are tied to the zones.
What building work is affected?
These changes only affect new construction or existing properties. Tenancy retrofit insulation standards are separate and not covered by the Building Act and Building Code. See more on how H1 applies to building work on existing buildings here
When are the changes happening?
Improvements to the requirements under H1 were published by MBIE in November 2021 and, more recently, the transition periods for housing were updated.
Three key things are needed to determine the new requirements a building is subject to:
1. The building type
Is it housing, a buildings up to 300m2 or a building greater than 300m2?
2. Site address
The site address of the building to determine which of six new Climate Zones it’s in.
When the consent application will be submitted.