Step 2: Applicants consider current and proposed Building Code compliance for the whole building

Building consent applicants need to consider Building Code compliance for the whole building to check it continues to comply to the same extent as before the alteration – and to identify which fire and accessibility clauses need to be looked at further. 

For buildings subject to section 112 or 133AT of the Building Act, building consent applicants need to consider and demonstrate the following in their application:

Section 112

  1. That the building as whole (not only the part being altered) will continue to comply with all clauses of the Building Code to the same extent as before the alteration.
  2. Whether the building as a whole will comply fully with any of the fire and accessibility Building Code clauses after the proposed alteration. An assessment of 'as nearly as is reasonably practicable' (ANARP) (Step 3) will apply to any Building Code clauses that the building does not comply with.

Section 133AT (earthquake-prone building)

  1. That the building as whole (not only the part being altered) will continue to comply with all clauses of the Building Code to the same extent as before the alteration.
  2. Whether the building as a whole will comply fully with any of the fire and accessibility Building Code clauses after the proposed alteration. An assessment of ANARP (Step 3) will apply to any Building Code clauses that the building does not comply with.
  3. That the proposed alteration includes seismic work so that the building is no longer earthquake prone after the alteration (if it is a substantial alteration).

BCAs will check this information.

1. Demonstrating compliance with all Building Code clauses to the same extent

Building consent applicants should provide adequate evidence including plans, drawings and previous compliance documentation to demonstrate that the building's overall compliance with the Building Code will not be reduced by the alteration. In most cases this will be a straightforward test.

  • If the building complies with provisions of the Building Code before the alteration, it must continue to do so. If the building exceeded the requirements of the Building Code before the alteration, the Building Act does not prevent the alterations resulting in a lesser level of performance, as long as the building continues to comply with the provisions of the Building Code.
  • If the building did not comply fully with the Building Code before the alteration, it needs to comply to the same extent that it did before the alteration.

For example, Determination 2017/019 considers whether proposed alterations to a school toilet block, with a reduced number of toilets, will comply with the Building Code to the extent required.

  • If the building complied with the Clause G1 of the Building Code before the alteration then the number of accessible toilets may be reduced, so long as the building still complies with this aspect of the Building Code after the alteration.
  • If the building did not comply before the alteration then the number of accessible toilets must not be reduced by the alteration.

An alteration may require an existing building element to perform better in order to meet this requirement. For example, if a proposed alteration includes new building work to an existing building element (ie new cladding over an existing frame) the new work would require fixings to the existing frame. If the existing frame is not compliant, eg it has rot, those fixings will not comply (as new building work) if they are into rotten wood. In this scenario, the frame needs to be remedied in order for the new cladding to comply.

Determination 2017/019

2. Demonstrating compliance with fire and accessibility Building Code clauses 

MBIE suggests completing a table to outline the applicable Building Code clause, and the means of compliance. The threshold for ANARP will be assessed (in Step 3) for any Building Code clauses where full compliance is not demonstrated. 

Examples tables for outlining applicable Building Code clauses and means of compliance.

Complying with the fire provisions
Relevant Building Code clauses Ways to demonstrate compliance* Building as a whole complies () and means of compliance (relevant AS, VM or an alternative solution) OR Building as a whole does not comply (X)
Acceptable Solution (AS) Verification Method (VM)
C3.4 Fire affecting areas beyond the fire source C/AS1-AS7 C/ VM2 Eg C/AS1
C4 Movement to place of safety C/AS1-AS7 C/ VM2  
C6 Structural stability C/AS1-AS7 C/ VM2  
D1 Access routes D1/AS1
NZS 4121:2001
-  
F6 Visibility in escape routes F6/AS1 -  
F7 Warning systems F7/AS1 -  
F8 Signs F8/AS1 -  

 

Complying with the accessibility provisions
Relevant Building Code clauses Ways to demonstrate compliance* Building as a whole complies () and means of compliance (relevant AS, VM or an alternative solution) OR Building as a whole does not comply (X)
Acceptable Solution (AS) Verification Method (VM)
D1 Access routes D1/AS1
NZS 4121:2001
D1/VM1 Eg NZS 4121:2001
D2 Mechanical installations for access D2/AS1-AS3
NZS 4121:2001
-  
F7 Warning systems F7/AS1
NZS 4121:2001
-  
F8 Signs F8/AS1
NZS 4121:2001
-  
G1 Personal hygiene G1/AS1
NZS 4121:2001
-  
G2 Laundering G2/AS1
NZS 4121:2001
-  
G3 Food preparation and prevention of contamination G3/AS1
NZS 4121:2001
-  
G5 Interior environment G5/AS1
NZS 4121:2001
-  
G9 Electricity G9/AS1
NZS 4121:2001
G9/VM1  
G12 Water supplies G12/AS1-AS2
NZS 4121:2001
G12/VM1  

*Applicants can also demonstrate compliance by using an Alternative Solution

If the building will fully comply with all required Building Code clauses for fire and accessibility after the proposed alteration, no ANARP assessment is needed. Proceed to Step 4.

Additional resources

Previous advice issued by MBIE on requesting information about means of escape from fire for existing buildings sets out factors that indicate the likelihood of a building complying with the current Building Code requirements for fire. These include:

  • building age
  • information held on the building by the BCA and/or territorial authority.

Requesting information about means of escape from fire for existing buildings

Consider the key factors has more details on how to use this information.

Alternative solutions for compliance with the Building Code has further information.

3. Establishing compliance with substantial alterations requirements for earthquake-prone buildings subject to section 133AT

For proposed alterations subject to the substantial alterations requirement to include seismic work, it is expected that a structural engineer will indicate in their documentation the performance level intended to be achieved by the seismic work. This will be used to determine that after the alteration the building will no longer be earthquake prone.  

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This information is published by the Ministry of Business, Innovation and Employment’s Chief Executive. It is a general guide only and, if used, does not relieve any person of the obligation to consider any matter to which the information relates according to the circumstances of the particular case. Expert advice may be required in specific circumstances. Where this information relates to assisting people: