The 2020-2021 NZBC changes were published by MBIE on the 5th November 2020 with a 12 month transition period ending on 3rd of November 2021. During the transition period the old versions or new and amended versions of the Acceptable Solutions and Verification Methods can be used, but from the end of transition only the new and amended versions can be used, with the pre-amended versions becoming Alternative Solutions.
Changes included two new Acceptable Solutions and amendments to twelve existing Acceptable Solutions and Verification Methods. In total, there were 27 amendments across 12 documents.
Changes involve the following Acceptable Solutions and Verification Methods:
- C Protection from Fire: C/VM2, C/AS1, C/AS2
- E1 Surface Water: E1/VM1, E1/AS1, plus new E1/AS2
- E2 External moisture: E2/AS1
- E3 Internal moisture: E3/AS1 plus new E3/AS2
- G9 Electricity: G9/VM1, G9/AS1
- G13 Foul Water: G13/AS1, G13/AS2, G13/AS3
Summary of changes
The following is a brief description of the changes to new and amended Acceptable Solutions or Verification Methods. Included are links to additional articles that provide more detail for some complex areas. We have also included a brief description of the effects on Masterspec sections.
C PROTECTION FROM FIRE: C/VM2, C/AS1, C/AS2
C/VM2 (amendment 6), C/AS2 (amendment 2) - Cladding Testing
New Standards for testing are:
- AS 5113: 2016 (+A1) - Classification of external walls of buildings based on reaction-to-fire performance. (previously in comments)
- BS 8414.1: 2015 (+A1) - Fire performance of external cladding systems - Test method for non-loadbearing external cladding systems applied to the masonry face of a building. (previously in comments)
- BS 8414.2: 2015 (+A1) - Fire performance of external cladding systems - Test method for non-loadbearing external cladding systems fixed to and supported by a structural steel frame. (previously in comments)
- BS EN 13501.1: 2018 - Fire classification of construction products and building elements - Classification using test data from reaction to fire tests. (new version AS2) (previously in comments)
- NFPA 285: 2019 Standard fire test method for evaluation of fire propagation characteristics of exterior wall assemblies containing combustible components. (new version)
- BR 135: 2013 Fire performance of external thermal insulation for walls of multistorey buildings - Third Edition. (previously in comments)
The use of the new Standards works in tandem with defined building heights and distances from boundaries. The heights are;
- ISO 13785: 2002- Reaction-to-fire tests for facades - Intermediate-scale test. (from VM2)
- BRANZ Study Report No. 137: 2005 Development of the Vertical Channel Test Method for Regulatory Control of Combustible Exterior Cladding Systems. (from VM2)
Combustibility takes on a new complexion with the addition of BS EN 13501.1. This introduces and defines "Non-combustible" classified as A1 to the Standard, and "Limited Combustibility" classified as A2 to the Standard. These classifications are common in related European product data sheets. Limited combustible and non-combustible materials can be used without restrictions as claddings and wall cladding systems (if forming all substantive components of a wall cladding systems), which has the potential to make it easier and cheaper to comply.
- Under 10m (C/AS1 is 10m and under)
- Under 25m
- 25m and over
Cavity Barriers are now better defined.
C/VM2, amendment 6 - Horizontal fire Spread & Editorial amendments
A number of new figures and tables have been added relating to:
- Configuration of buildings/walls and relationship to boundaries with regard to openings & protection
- Glazing & openings and calculation methods
- Note, sprinkler options for unprotected areas is further restricted
There has been a considerable amount of text relocated from the Commentary Documents into C/VM2
C/AS1, amendment 5
A number of changes to definitions including those related to Escape. Note, clause 1.1.1.b. will limit escape height to 4m for multi-unit dwellings under C/AS1.
C/AS2, amendment 2
There are a large number of both major and minor changes. For more information on the changes to C/VM2 and C/AS2 read our focus article here.
The requirements for insulation clearance from recessed lights has been deleted from NZBC C/AS2 clause 7.4, and transferred to NZBC G9 Electricity. See G9 below for comments on recessed lights, for more detail.
Masterspec has updated effected sections, which among other things involved dealing with a considerable number of reference changes in NZBC C/AS2.
E1 SURFACE WATER: E1/VM1, E1/AS1, PLUS NEW E1/AS2
E1/AS1, E1/VM1, amendment 11 - Standards
A number of Standards updated to newer versions.
E1/AS2 - New Acceptable solution
MBIE finally (at last!) added AS/NZS 3500.3: 2018 Stormwater Drainage, as a new Acceptable Solution. The new E1/AS2 of course, modifies 3500.3, a few are significant (but not all bad). AS/NZS 3500.3 creates more options, extending the scope, range, and possibilities over E1/AS1. We understand from industry sources that it certainly helps provide more accurate calculations for rainfall provisions.
This all provides a valuable new tool to the toolbox and Masterspec has certainly taken advantage of this by adding AS/NZS 3500.3 as an option to the appropriate sections.
E1/AS1, E1/VM1, amendment 11 - Changes in Rainfall Intensity Requirements
E1/VM1 has more rainfall intensity sources added.
E1/AS1 Appendix A, Rainfall Intensity - the original maps have been replaced by extensive tables providing rainfall intensities for locations all over New Zealand, including their Annual Exceedance Probability (AEP).
Masterspec has updated effected sections, which mainly involves separating clause for using AS1 or AS2.
For more information on the new E1/AS2 and the changes to E1/AS1 and E1/VM1 read our focus article here.
E2 EXTERNAL MOISTURE amendment 10
E2/AS1 has mainly been updated to align with the new E1/AS2, so there has been little effect on Masterspec sections.
Note that free board for internal gutters in clause 18.104.22.168 has been increased from 20mm to 30mm. This aligns with the freeboard requirement in the new clause of E1/AS1, 5.1.5.
E3 INTERNAL MOISTURE: E3/AS1, PLUS NEW E3/AS2
E3/AS1 amendment 7
New Standard added for testing of overflows - BS EN 274.2.
Sanitary Appliances (washing machines, dishwashers etc) have been added to definitions. Sinks and Tubs have been added to the definition of Sanitary Fixtures (previously thought not to be).
Amendments have generally added more restrictions for:
- Sanitary Fixtures that could overflow and damage an adjoining household unit or other property.
- Floor and wall lining materials for spaces containing Sanitary Fixtures and/or Sanitary Appliances (very few options for floors)
- Sealing of penetrations (taps, mixers, roses etc) in showers and showers over baths
- Edge details for baths with showers over.
The reduction of acceptable options for floors and walls could prove problematic in some instances like:
- Random changes in floor material to suit the E3/AS1 rather than the building design
- Trying to get BCA approval for a timber floor in a kitchen in a single level detached house
- Trying to get BCA approval for a timber linings that the dishwasher is installed next to
Floor and wall linings not mentioned in E3/AS1, although they may be suitable, will be Alternative Solutions, which then becomes a matter of interpretation by the BCA.
In clause 3.3.1 and 22.214.171.124 the height of an impervious wall lining above the shower rose has been changed from a minimum of 300mm to 50mm. However Figure 5 has not changed and still shows 300mm, we assume this is an oversight?
Masterspec has updated effected sections, which mainly involves sections related to sanitary fixtures and tapware.
E3/AS2 - A new Acceptable Solution
This new Acceptable Solution cites the Waterproofing Membrane Association Inc's, Code of Practice for Internal Wet-areas Membrane Systems, as an Acceptable Solution for substrate waterproofing. The new E3/AS2 of course slightly modifies the Code of Practice (CoP), but E3/AS2 clause 1.2, also identifies items in the CoP that exceed the NZBC clauses E3.3.2 - E3.3.6. If you are using E3/AS2, then it is important to understand clause 1.2, as exceeding NZBC is optional not mandatory.
It is important to note that the CoP puts a number of restrictions and requirements on substrates for membranes.
Masterspec has updated a considerable number of sections related to wet area membranes and membrane substrates.
You can download the CoP in AS2 here (as a pdf)
For more information on the new E3/AS2 and the changes to E3/AS1 read our focus article here.
G9 ELECTRICITY: G9/AS1, G9/VM1
G9/VM1 amendment 7
The Electrical (Safety) Regulations 2010 (no reprint date given) has become the controlling document in G9, replacing AS/NZS 3000 and other Standards as the cited document. However, this does not change things as much as you would think, as the Regulations mostly refer to the same AS/NZS 3000 and other Standards anyway.
The Electrical (Safety) Regulations 2010 (latest reprint as at 21 Jan 2019) cites AS/NZS 3000:2007, not the latest version AS/NZS 3000:2018. Unlike the 2007 version, the 2018 version covers more recent electrical developments like, EV charging, modern types of recessed light fittings etc. In most cases the two versions are the same or very similar. However to specify "modern items" you need the modern Standard. So Masterspec uses AS/NZS 3000:2018 generally, but provides some guidance for those very few occasions where the two versions cover a subject but differ (allows Alternative Solutions to be assessed).
G9/AS1 - Proposed amendments to G9/AS1
Still cites NZECP 51, but at least it now clarifies how limited the use of it is (about time?). NZECP 51 is only for very limited work by an owner of a residential property, but realistically virtually all projects would require an electrician and licensed inspector. This means that most electrical work would be done under G9/VM1.
The amendment also adds items to the requirements of buildings intended for use by persons with disabilities, these include:
- heights for light switches have been defined
- In accessible accommodation, switches & outlets will need to be "contrasting to surrounding"
- Clarification that the Electrical (Safety) Regulations 2010 take precedence if there is conflict, for instance outlets in wet areas etc.
As the requirements for insulation clearance from recessed lights has been deleted from NZBC C/AS2 clause 7.4, and transferred to G9 and thus ending up with the requirements of AS/NZS 3000. Unlike the old requirement in C/AS2, AS/NZS 3000:2018 (see G9/VM1 above), except for two types, does not differentiate between residential and commercial complying recessed light fitting types. So both can now have insulation abutting or covering the fitting depending on the type of fitting.
AS/NZS 3000:2018 covers the same fitting types as AS/NZS 3000:2007, plus a few additional more modern types.
Masterspec has updated all electrical related sections to the amended Acceptable Solution and Verification Method, particularly for recessed light fittings and the requirements of buildings intended for use by persons with disabilities. We have also taken the opportunity to do general updates to do with; arc fault detection devices (AFDD) , wet area fittings, exterior fittings.
With the updated use of AS/NZS 3000:2018 bringing in some additional recessed light fitting types, Masterspec has updated the clearance to insulation requirements in the Masterspec insulation sections.
G13 FOUL WATER: G13/AS1, G13/AS2, G13/AS3, amendment 9
G13/AS1, G13/AS2, G13/AS3 - Generally
A number of Standards updated to newer versions.
G13/AS3 amendment 9
G13/AS3 modifications to AS/NZS 3500.2 have increase, particularly related to drain junctions in AS/NZS 3500.2. Note, AS/NZS 3500.2 section 14, Multi-Unit Developments has been deleted by G13/AS3.
G13/AS3 has had "Sanitary" added to the title and will read as "Sanitary Plumbing and Drainage".
Part 1.0 Installation of PVC-U Pipe which cites AS/NZS 2032, has been deleted and not replaced.
Masterspec updates to related sections has been relatively minor, with some major changes to clarify backfilling to G13/AS2 or AS/NZS 3500.2.
Go here to read a full list of the work sections affected by the changes.