The price inflation for building products has slowed markedly in recent months but the cost to build a 3-bedroom home remains over 40% higher than it was in 2019. There is also evidence that construction costs here are higher than in other countries such as Australia.
The Commerce Commission’s residential building supplies market study, undertaken at the height of the price inflation in 2022, found that competition for the supply of building materials was not working as well as it could. The study made a number of recommendations, including updating more Acceptable Solutions and Verification Methods, and having more certification schemes that can issue product certificates deemed compliant with the New Zealand Building Code.
Building products and specifications
The government amended the Building Act this year to provide new pathways for overseas building products to be used in New Zealand. A key one is the introduction of the Building Product Specifications – effectively a list of all the building product standards that meet or exceed the Building Code. Sections of the Building Product Specifications will be referenced by Acceptable Solutions and Verification Methods to demonstrate compliance for a particular Building Code clause.
MBIE gives an example of how it will work. In H1/AS1, where today it says: ‘The thermal resistance (R-values) of insulation materials may be verified by using AS/NZS 4859.1’ in future, H1/AS1 will say: ‘The thermal resistance (R-values) of insulation materials shall be determined by using the methods in section 3.5.1 of the Building Product Specifications for the given types of insulation’.
The first edition of the Building Product Specifications will not cover all building products. MBIE will update and expand the document regularly to incorporate more building product standards that are currently referenced in Acceptable Solutions and Verification Methods. It will also add overseas building product standards that are assessed as requiring equivalent or better performance.
Welcome move, but devil is in the details
Karla Falloon, BRANZ Director Office of the Chief Executive, says BRANZ is supportive of the new initiatives to reduce costs as long as it does not come at the expense of quality.
Some overseas product certification schemes may be easy for us to accept without problem. For example, much of the plumbing in Australian and New Zealand homes is broadly similar, and the 200,000 products certified under the Australian WaterMark certification scheme may be readily accepted here.
In other areas, MBIE will need to take care ensuring that overseas schemes are relevant to New Zealand.
Construction methods vary between countries. While most New Zealand homes have a timber frame and many have timber cladding, in European countries, steel, concrete and brick are more commonly used. The fire risk is very different between timber-framed and clad homes and concrete homes.
Our climate is our own. For example, the UV Index in New Zealand is commonly around 12 in summer and 13 or more in the Far North (16.8 has been recorded). In the UK, a figure of 8 is rare. Our high UV levels can have a big impact on the durability of exterior materials.
We’re the Shaky Isles. Earthquakes over magnitude 5 are not uncommon – we had 10 in 2023 – while European countries rarely or never experience them. Some of our building materials must provide bracing for earthquakes and wind to a much greater degree than is the case overseas.
Martin Gordon, GM Consultancy Services at BRANZ, says that fire, structure and durability are among the areas of greatest risk with building materials here and our requirements in these areas can be comparatively high. He points out that, if a product has been tested in the UK for 3,000 hours at a certain UV level but the test requirement in New Zealand is for 7,000 hours at a higher UV level, the UK test results won’t apply here.
Given BRANZ’s work in Appraisals and as a CodeMark assessor and its history supporting standards development, the organisation could potentially have a role to play.
Right place, right installation crucial
BCAs must already accept products and methods with CodeMark certification as being Building Code compliant provided the product or method is used in accordance with details noted on the certificate. This qualification will also apply to newly MBIE-recognised products certified under an overseas certification scheme.
This is an extremely important point. If an architect, designer or builder selects the wrong product for a particular use or it is installed incorrectly, they may be liable if the product fails. The recent amendment to the Building Act provides good-faith liability protection to BCAs regarding the Building Product Specifications and for products certified overseas that are recognised by MBIE.
Will specifiers and importers run with the ball?
As suggested in the article What opening the market means in Build 205, for higher-risk elements such as cladding or structural components, architects, designers and builders may be reluctant to specify unfamiliar products. Karla Falloon points out that they need to look at systems as a whole to see how new products work in conjunction with the products around them.
Commercial judgement will still apply. We are a comparatively small market, shipping costs are still higher than before COVID and supporting technical literature will need to be developed for New Zealand construction.
Importers may not bring in some new products if they consider the likely business will not offset the costs.
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Articles are correct at the time of publication but may have since become outdated.
