Removing impediments to product substitution and variation
Making the process for product substitutions and variations to consented building work more effective and efficient supports competition in building products, can help to reduce the time, cost, and complexity to build, and supports desirable outcomes for the building consent system.
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While current processes help to prevent inappropriate product substitutions and ensure code compliance, there is scope for improvement.
MBIE identified a package of options that responds to recommendation 4 of the Commerce Commission’s market study into residential building supplies. This is supported by new minimum building product information requirements that commenced in December 2023. The package of options comprised:
- Exploring ways to reduce specification by brand
- monitoring and updating (if needed) recently issued product substitution guidance[1]
- amending the building consent form to add a place for applicants to specify suitable alternative products (if they choose to)
- clarifying the definition of a ‘minor variation’ to a building consent in regulations.
- Increasing the flexibility of the MultiProof scheme:
- Updating the current MultiProof guidance and creating a definition in regulations allowing for ‘minor customisations’ to be made to a MultiProof before consent, using the definition of a ‘minor variation’ to a building consent as a starting point.
Submitters were asked whether they agreed with the preferred approach (i.e. progress all proposed options as a package), for their views on impacts and any risks and mitigations, and whether they considered other options were worth exploring.
Figure 3: Do you agree with the preferred approach?
Text description: Figure 3
MBIE received 202 submissions on this chapter. 97 submitters agreed and 62 somewhat agreed with the preferred approach. There were 22 submitters that did not agree.
Impacts, risks and mitigations
Some common themes raised in submissions on the preferred approach for product substitution and variations to consents, and MultiProof, included:
MBIE should carefully consider product performance
112 submitters – regardless of whether they agree with the preferred approach – commented on the importance of carefully considering the performance of a product when substituting building products.
Clear guidance and rules are crucial
A large number of submissions also raised the importance of having clear guidance alongside clear rules to ensure there is consistency across applicants and building consent authorities as to what constitutes a suitable alternative to a building product.
Submissions commented on the key role that clear guidance plays in clarifying what the rules mean (i.e. legislation and regulations), and how they should be applied by both applicants and building consent authorities. This includes MultiProof, for which submissions asked for clear guidance and education to raise awareness and understanding of the scheme across the industry and building consent authorities, and for MBIE to create a definition of ‘minor customisation’.
There were mixed views on the proposed option to modify building consent forms and MultiProof
Submitters suggested in response to the proposed option to modify building consent forms to add a place for applicants to specify suitable alternative products, that it was likely, at least in the short term, to increase upfront processing time and cost. Some submitters commented that they preferred ‘dual specification’ rather than making variations to consents easier to avoid any issues later on should defects arise. It was suggested that ‘dual specification’ should be done through the consent application’s supporting documentation rather than by amending the building consent form. Other submitters preferred that the consent forms remain unchanged.
Some submitters suggested that the Building (Forms) Regulations 2004 need to be reviewed as the consent forms seem outdated, with no requirement for building consent authorities to capture and, later on, share information.
11 submitters commented that current uptake on MultiProof was low. However, there was significant support for the options to increase the flexibility of MultiProof – submitters generally commented that the proposals would likely help streamline the building consent system. It was also suggested that defining a ‘minor customisation’ to a MultiProof could effectively defeat the purpose of a MultiProof certificate and create confusion for applicants and building consent authorities.
Other issues and impacts
Inspections
Some submitters commented that there needs to be quality inspections to ensure substitutions and installations onsite are compliant. A few submitters supported remote inspections, facilitated by technology, as some inspections require inspectors with specific competence who may not be available. Others suggested inspectors should approve minor variations onsite, which could become part of an inspector’s training requirement.
Alternative options
Submissions raised several options that were not part of the preferred approach. Common suggestions were:
- Creating more alternative compliance pathways to support applicants to get a building consent. Chapter 5 of the options paper included proposals for new assurance pathways. However, the building code and acceptable solutions and verification methods are out of scope of this review.
- Consider compulsory insurance for designers or 'non-approved' building products so that liability does not rest on building consent authorities, but rather the designers choosing a replacement product are accountable and liable for potential building failures.
- MBIE to create and maintain a national product register to make it easier for applicants and building consent authorities to know which products are considered suitable alternatives. The concept of a national register of building products has previously been considered as part of earlier building consent reforms in 2021.
- New building product information requirements that commenced in December 2023 require manufacturers or importers to make a statement about how their building product may contribute to building code compliance and to disclose that information online.
More Information
Product substitution guidance [PDF 6MB](external link) — Building Performance
Product Substitution - Plasterboard [PDF 1.3MB](external link) — Building Performance
Building Consent Guidance [PDF 2MB](external link) — Building Performance