Last updated: 2 November 2023
Recent changes to the Building Code support New Zealand to deliver safe, healthy and durable buildings.
Publication of new acceptable solutions and verification methods
MBIE has published updated acceptable solutions and verification methods that focus on plumbing and drainage, protection from fire and the structural stability of hollow-core floors.
This update was made following a consultation that received more than 100 detailed submissions and comments.
A summary of the decisions is provided below. We encourage you to read the outcome documents for additional information on the feedback we received and the decisions themselves.
We are supporting these changes by holding a webinar on 9 November 2023.
Plumbing and drainage
MBIE has amended the acceptable solutions and verification methods for E1 Surface Water, G12 Water Supplies, and G13 Foul Water to support plumbing and drainage work in New Zealand. These changes are the latest in a series of continuous improvements to ensure the Building Code compliance pathways for the plumbing sector are fit for purpose and up to date. This is to ensure New Zealanders have safe and reliable plumbing systems.
The update to G12/AS1 includes updating the limits for lead in plumbing products, reducing hot water temperatures, improving the requirements to protect potable water from backflow contamination and water supply system components.
The adoption of the latest version of the AS/NZS 3500 plumbing and drainage standards is a key part of these amendments. MBIE participated in the development of these standards and the new versions include a number of New Zealand-specific requirements, making some of the previous New Zealand Building Code modifications to the standards no longer necessary. These standards are cited as compliance pathways in several Acceptable Solutions.
Lead in plumbing products
The amended Acceptable Solution G12/AS1 to limits the maximum content of any product that contains copper alloys, intended for use in contact with potable water for human consumption. This includes products such as pipe fittings, valves, taps, mixers, water heaters, and water meters.
The transition period for this change will end on 1 September 2025. Extending the transition period to 2025 will provide certainty and direction to the sector and gives manufacturers and suppliers additional time to implement the required change to the effected plumbing products.
We indicated in our consultation proposal the intent to align the lead in plumbing products transition period for New Zealand with the time when equivalent requirements will come into force in Australia. The transition period end date for the introduction of equivalent requirements in Australia has recently been extended by 8 months to 1 May 2026.
Following consideration of the implications of the revised transition period end date in Australia, we can confirm that the transition period end date for the G12/AS1 lead in plumbing change will remain 1 September 2025.
MBIE has amended Acceptable Solution G12/AS1 to lower the maximum hot water temperature delivered at the tap for most buildings from 55°C to 50°C. The amendments also include additional temperature control devices to give plumbers more ways to limit hot water temperatures. These changes do not apply to hot water used in kitchens or laundries, nor to the minimum temperature of hot water in a storage tank. The changes apply only to fixtures used for personal hygiene in new plumbing systems. Homeowners should not adjust these temperatures themselves as there are health risks associated with setting the temperatures incorrectly. This work should only be performed by a plumber. These amendments have a 12-month transition period to ending on 1 November 2024.
Protection of potable water
The amendment to Acceptable Solution G12/AS1 to improve the requirements to protect potable water from backflow contamination. This has a 12-month transition period ending on 1 November 2024.
Plumbing and drainage Standards
MBIE has amended the E1, G12 and G13 acceptable solutions to cite the latest versions of the AS/NZS 3500 standards. The adoption of these standards is a key part of these amendments. MBIE participated in the development of these standards and the new versions include a number of New Zealand-specific requirements, making some of the previous New Zealand Building Code modifications to the standards no longer necessary. These standards are cited as compliance pathways in several acceptable solutions.
Water supply system components
MBIE has amended Acceptable Solution G12/AS1 to improve the requirements for plumbing components in water supply systems. MBIE has also amended Verification Method G12/VM1 to include a new design method to size water pipes.
Protection from fire
MBIE has amended Acceptable Solutions C/AS1, C/AS2, F7/AS1, and Verification Method C/VM2 to improve the safety of people from fire. The changes are a result of feedback received during the consultation process. The changes are a result of feedback received during the consultation process. The changes aim to increase the protection of people in residential homes from fire and bring the requirements for fire safety systems in line with the latest industry standards. These amendments have a 12 month transition period to ending on 1 November 2024.
The changes to Acceptable Solution C/AS1 require interconnected smoke alarms as the minimum fire safety system required in each household unit.
New versions of standards for sprinkler systems, fire alarm systems, interconnected smoke alarms, and smoke control systems have been cited in Acceptable Solutions C/AS1, C/AS2, F7/AS1 and Verification Method C/VM2. By aligning the requirements for fire safety systems with the latest industry standards, MBIE is ensuring that provisions in the compliance pathways for fire safety systems are up-to-date, consistent and clear.
New versions of the standards are already available on Standards New Zealand's website and can be used as part of an alternative solution to comply with the Building Code's protection from fire requirements. Free access to the fire alarm and interconnected smoke alarm standard is also sponsored by MBIE.
Standards New Zealand - standards.govt.nz
Structural stability of hollow-core floors
MBIE has removed the deemed to comply pathway in B1/VM1 for the design of the supports for hollow-core floor systems. We believe removing this deemed to comply solution from B1/VM1 will minimise the chance of poorly designed systems being specified in new building work.
This change for hollow-core floor systems will take immediate effect and there will be no additional transition period. This decision was announced in May 2023 prior to the publication of the revised verification method to provide certainty and direction to the sector.
Structural engineers looking to use these types of floors or provide advice to building owners should review the advice on hollow-core floors issued by Engineering New Zealand, the Structural Engineering Society New Zealand, and the New Zealand Society of Earthquake Engineering.
Advice on hollow-core floors - sesoc.org.nz
Transition period for insulation settings for new housing
Outcome of consultation Building Code update 2022 - Transition period for the energy efficiency of housing
The transition period for the H1 update ended on 1 November 2023. Refer to the H1 acceptable solution and verification methods for the minimum R-values that apply for roofs, floors, walls, windows and doors.
Webinar on H1 energy efficiency for housing and small buildings
On 4 August MBIE hosted a webinar to explain the recent changes to the H1 energy efficiency documents. MBIE were joined by BRANZ and The New Zealand Green Building Council , and discussed the compliance pathways for H1, what tools and information are available and some common construction details that can be used to comply.
Watch the H1 webinar recording - YouTube
Duration: 81 minutes and 49 seconds
A list of resources that are available to help explain the benefits of building and how to implement the changes is available on our website.
The Building for Climate Change programme will continue to build on the foundations set by these H1 amendments. The programme is currently developing methodologies, data and tools that would enable people to undertake operational efficiency assessments of buildings. These assessments intend to take a more holistic, outcomes-based view of building performance, and will contribute to reducing the sector's carbon emissions in line with the Government's climate change goals.
Background on the Consultation
In May 2022, MBIE consulted on acceptable solutions and verification methods for complying with the Building Code. This consultation closed on 1 July 2022 and received over 100 detailed submissions and comments.
Read the proposal documents - mbie.govt.nz
Webinar on the 2022 update
On 5 May 2022, MBIE hosted a webinar to discuss the proposed changes and answer questions about the consultation.
Duration: 59 minutes and 22 seconds
Duration: 32 minutes and 55 seconds
Next steps for energy efficiency in the Building Code
The changes to the insulation requirements represent an important first step for MBIE's Building for Climate Change programme. The changes will deliver warmer, drier and healthier homes that cost significantly less to heat and will also generate carbon savings through this energy efficiency.
MBIE is fully committed to working alongside the building and construction sector to ensure successful implementation of these important changes.
MBIE is working with key industry organisations to ensure that the building and construction sector has access to the information and education it needs to understand the changes and implement the new requirements.