30 Aug 2019

Masterspec has completed its review of the updates to the approximately sixteen Acceptable Solutions and Verification Methods.  Although one or two made it into sections for the August release, we have completed the majority of updates to Masterspec sections for this 1st September release.  The updates resulted in approximately 490 Masterspec sections requiring amendment; however, our Update Manager and this article should make it a little easier for you to keep up to date.

On the 27th June 2019, the transition period started for updates to the Acceptable Solutions and Verification Methods.  They will all become compulsory on the 1st November 2019, so from that point, if any previous versions of ASs or VMs are used they will be considered an alternative solution.

The following is a review of the main updates with comments from Masterspec, including significant additional material to our last interim report (1st Aug NOTES) on the updates:

B1 Structure: B1/VM1 (Amendment 18)

  • Paragraph 3.1.1: Hollow-core floor precast unit Maximum depth increased to 400mm.
  • Paragraph 3.1.2: Paragraph deleted - this removes the use of cast iron anchors & couplers (cast iron was already banned from 1 Nov 2018).
  • Paragraph 5.3: Light steel framing (using NASH Standard Part 1) deleted and moved to NZBC B1/AS1.

Masterspec sections updated where necessary.

B1 Structure: B1/AS1 (Amendment 18)
Paragraph 9.1: Is a new paragraph that adds light steel framing using the new NASH Standard Part 2 (was NZBC B1/VM1, 5.3).

NASH Standard Part 2: May 2019 Light Steel Framed Buildings is now included within B1/AS1 Structure, as an acceptable solution.  The previous reference to NASH Standard Part 1 within B1/VM1 has been removed.  NASH Standard Part 2 sets out non-specific design solutions for cold-formed steel-framing used in low-rise buildings including houses and commercial buildings.  NASH standard Part 2 does not cover the use of light steel framing for ground floor subfloor framing; instead, it references Standards in relation to concrete slabs and timber-framed subfloors.  The design of trussed roofs where used on buildings within the scope of the NASH standard part 2 are required to be designed in accordance with NASH Standard Part 1 as a specific engineered design.  Masterspec sections, particularly those based around 3421 LIGHT STEEL FRAMED BUILDINGS, have been updated to reflect these changes to the acceptable solutions and verification methods.


NASH Standard Part 2 -

B2 Durability: B2/AS1 (Amendment 11)

  • Paragraph 3.6.2: Adds the new NASH Standard Part 2.
  • Paragraph 3.6.3: Modifies clause 3.1 of the NASH Standard Part 2.


C Protection from Fire: C/AS2 (the new C/AS2 edition replaces the old C/AS2 to C/AS7)
This is a new document that replaces the six old documents C/AS2 to C/AS7.  Note that C/AS1 remains unchanged.
Most of the text etc. remains the same although they might have been moved about (& renumbered), some clause text has been put into new tables, and there are a few new Standards.

Significant changes to the text:

  • New Zealand Fire Service now called Fire and Emergency New Zealand.
  • Fire Safety Systems: New Table 2.2 (was Table 2.1) & paragraph A2.1.1, add a new Fire Safety system, Type 15 - Fire & Emergency New Zealand Lift Control.  This is for control of lifts under fire conditions to NZS 4332 Non-domestic Passenger and Goods Lifts.
  • Paragraph 3.10.2.d.ⅲ): adds that, under some conditions, a space for sanitary fixtures in an exitway has no floor area limits.
  • Paragraph 3.15.6.b): adds that ward bedroom egress doors do not need vision panels.
  • Figure 3.21: Open balustrade 1100mm height changed from maximum to minimum.
  • Paragraph 4.6.2: has added that for Group Sleeping, subdivision of firecells may be allowed.
  • Paragraph 4.18.1: Old paragraph deleted, which removes, that an activated alarm must turn off all A/C and ventilation systems.  The change clears up that not all systems need turning off; however, the new 4.18.1 (old 4.18.2) still requires smoke control for some systems.
  • Figure 4.17: "Fire Doors to Separate Floors Above & Below Final Exit Level" now shows only 1 door (was 2 doors).
  • Paragraph 5.2.2 deleted, which removes the dispensation for cladding within 1m of a boundary if sprinklers are used.
Major changes to Tables:
  • Old Table 2.0 is now Tables 2.2. a) to d) (for different Risk Groups), and is fire safety systems relative occupancy & height, the new text is the same but with added notes
  • Old Table 4.1 for surface finishes (group numbers) has been split in 2 and renumbered.  New Table 4.3 is Internal Surface Finishes, which covers walls and ceilings. New Table 4.4 is Surfaces of Building Services (more detailed than the old table), covers the interior of ducts and exterior of pipes & ducts.
  • The old Table 4.2 Critical Radiant flux for floors, is now Table 4.5 but virtually the same.
  • Old Tables 5.2 and 5.3 are now Tables 5.2/1 to 5 and 5.3/1 to 5, that is 5 tables for each different Risk Group
  • Old Appendix C, Table C1 "Alternative Test or Classification Standards for Group Numbers", is now Table C1.1 and is unchanged.
  • Old C/VM2 Table A1, about acceptable generic material Group Numbers, has been added as C/AS2 Table C1.2, with minor alterations such as adding tiling.
Paragraph text converted to Tables:
  • 2.1(2.1.1,2.1.2) to Table 2.1 Fire Cell Floor Area Limits
  • 2.2 to Table 2.3 Fire systems for other firecells in building
  • 5.8.1 to Table 5.5 for external cladding system requirements, standardises the height to above or below 10m (deletes old 7m option).  Adds new Standard AS/NZS 3837

Major changes to Standards:

  • For fire dampers in clauses 4.16.12 & 4.16.14, AS/NZS 1668.1 "The use of ventilation and air conditioning in buildings - Fire and smoke control in multi-compartment buildings", has been replaced by AS 1682.1 Fire Dampers - Specification, and AS 1682.2 Fire Dampers - Installation.
  • Ductwork Standards AS 4254.1 "Ductwork for air-handling systems in buildings - Flexible duct", and AS 4254.2 "Ductwork for air-handling systems in buildings - Rigid duct", are added to the new Table 4.4.
  • Fire test Standard AS/NZS 3837 "Method of test for heat and smoke release rates for materials and properties using an oxygen consumption calorimeter", has been added to new Table 5.5.

A large number of Masterspec sections have been updated to reflect these changes to the new NZBC C/AS2.



E2 External Moisture: E2/VM2 (new VM)
A new VM that introduces a new cladding system test option using the BRANZ EM7 Test Specification, as another means of complying with NZBC E2.3.2.  Note that this new test allows cladding systems up to 25m in height, whereas apparently, the NZBC E2/VM1 simpler tests are only up to 10m.
Masterspec sections have not been updated to include this yet, but expect E2/VM2 to be introduced gradually as the industry adjusts to the new test.


G4 Ventilation: G4/AS1 (new AS1 edition, replaces old AS1)
New Clause 1.2.5 makes it mandatory for household units and accommodation units to have mechanical extract fans for showers/baths (25 L/s) and cooktops (50 L/s).   Passive Stack Vents have been effectively deleted from G4/AS1.
Note; these changes were made last month to the relevant Masterspec sections, in particular, those based around 7612 RESIDENTIAL EXTRACT SYSTEMS.


G12 Water Supplies: G12/VM1, G12/AS1, G12/AS2  (Amendment 12)
The change mostly revolves around the adoption of new versions of AS/NZS 3500.1 & AS/NZS 3500.4.  There has been very little change within the text of G12/VM1, G12/AS1 and G12/AS2.

  • AS/NZS 3500.1:2018, Plumbing and drainage - Water services, has replaced the old AS/NZS 3500.1:2015.
    The new 2018 version has several changes including; testing and commissioning of rainwater systems and a number of additional items for non-drinking water systems, etc.  Although these particular parts of AS/NZS 3500.1 are not referenced in G12/VM1, G12/AS1 and G12/AS2, they would be beneficial for designing and specifying those sorts of systems.
  • AS/NZS 3500.4:2018, Plumbing and drainage - Heated water services, plus Amendment 1, has replaced the old AS/NZS 3500.4:2015.
    The new 2018 version has a number of changes including:
    • Additional information on Expansion Vessels under 5.9 and a new Appendix P
    • Addition of a new section 10 on forced Circulatory Heated Water Reticulation.  Besides the technical requirements, it is worth noting that it also includes restrictions on the location of circulatory piping, as opposed to branch piping.  For instance, in an apartment block, common circulatory pipes should generally be in the common areas and only the branch pipe in the private apartment.

These particular new parts (and the rest) of AS/NZS 3500.4 apply to G12/VM1 through G12/VM1 clause 1.0.1.b), however, they are not referenced in either G12/AS1 and G12/AS2.

Masterspec sections have been updated to reflect these changes, although they generally exclude circulatory systems.

NZBC G12 -

G13 Foul Water: G13/AS1, G13/AS2, G13/AS3, G13/VM2  (Amendment 8)
This mostly revolves around the adoption of a new version of AS/NZS 3500.2.  

  • AS/NZS 3500.2:2018, Plumbing and drainage - Sanitary plumbing and drainage has replaced the old AS/NZS 3500.2:2015.
    The new 2018 version adds renovation of existing pipe systems, allowing the repair and upgrading of existing drains with various pipe liners including cured-in-place pipe (CIPP) liners.
    G13/AS3 allows the use of most of AS/NZS 3500.2:2018, and although G13/AS3 has not changed much, items of note (reminders) are:
    • G13/AS3, 2.0.1 excludes the use of AS/NZS 3500.2, section 14 Multi-Unit Developments
    • G13/AS3, 2.0.2 excludes the use of AS/NZS 3500.2, clause 3.19 Common Effluent Drainage Systems, and clause 5.6 Drains in Other than Stable Ground (unless specific design).
    • G13/AS3, 2.0.1 includes the use of the recently added AS/NZS 3500.2, section 16 on Vacuum Drainage Systems, this is applicable when soil/waste fixtures are lower than gravity drains or fixtures cannot be connected with a gravity system using acceptable falls, etc.  Design of these systems is very complex and precise; specialist advice is recommended.

Masterspec sections have been updated to reflect these changes, although they generally exclude pipe liners and vacuum systems.

NZBC G13 -