Determine whether your plumbing and drainlaying can be self-certified

What qualifies for the self-certification for plumbing and drainlaying scheme (and what does not)

Plumbing and drainlaying that can be self-certified is set out in the Plumbers, Gasfitters, and Drainlayers (Self-certification and Certificate of Compliance Information) Regulations 2026 (the self-certification regulations).

Plumbers, Gasfitters, and Drainlayers (Self-certification and Certificate of Compliance Information) Regulations 2026 – legislation.gov.nz

Step 1: Determine whether the building is in scope

The building is a qualifying building if:

• it is three storeys or less
• does not contain apartments.

If either requirement is not met, the work is not self-certifiable.

If the building meets both requirements, proceed to step 2.

Step 2: Confirm the work is plumbing or drainlaying

The work must fall within the statutory definitions of sanitary plumbing or drainlaying in the Plumbers, Gasfitters, and Drainlayers Act 2006. Civil works that are a part of the public network or network utility operator do not apply.

If the plumbing and drainlaying work can be consented under a building consent, proceed to step 3.

Step 3: Determine whether the work is specifically excluded

Certain plumbing and drainlaying is excluded under the scheme.

Examples include:

• plumbing penetrating fire separations
• plumbing in a common wall
• work outside the legislative definition
• alternative solutions (except on qualifying on-site systems).

If the work is not specifically excluded, the plumbing or drainlaying work can be self-certified.

Note: Where plumbing and drainlaying work is completed in stages or under separate building consents, some work may be eligible for self-certification while other work may not be. Even where work is eligible, it may not be proposed for self-certification and may instead follow the usual BCA inspection process.

Where the plumbing or drainlaying work does not fully meet the requirements of the nominated Acceptable Solution or Verification Method, the work may be self-certified up to the point where it deviates from the Acceptable Solution or Verification Method.

This should be made clear to the building consent authority (BCA) through the building consent drawings, schematics, and specifications.

If the work is excluded, the work is not self-certifiable. 

If the work is not specifically excluded, proceed to step 4.  

Step 4: Determine whether there is an applicable Acceptable Solution or Verification Method to show compliance with the Building Code

Common compliance pathways include:

• B2/AS1
• G12/AS1, G12/AS2 and G12/AS3
• G12/VM1
• G13/AS1, G13/AS2 and G13/AS3
• G13/VM1 and G13/VM4
• G14/VM1. 

If yes, proceed to step 5.

If no, proceed to step 6.

Step 5: Confirm that the work is designed according to the applicable Acceptable Solution or Verification Method

If an applicable Acceptable Solution or Verification Method exists, the work must be designed in accordance with it to be eligible for self-certification.   

Designers and building consent applicants ensure that the proposed self-certifiable plumbing/self-certifiable drainlaying is designed according to the applicable Acceptable Solution or Verification Method.  

Building consent authorities check to make sure the proposed self-certifiable plumbing/self-certifiable drainlaying is designed according to the applicable Acceptable Solution or Verification Method.  

Endorsed plumbers and drainlayers only self-certify plumbing and drainlaying designed according to the applicable Acceptable Solution or Verification Method (unless it’s a qualifying on-site system). 
This can be demonstrated through the applicant Form 2, drawings, schematics and specifications.  
 
If yes, the work can be self-certified.  

If no, proceed to step 6. 

Step 6: Determine if the work qualifies for the on-site system exception

On-site systems may remain self-certifiable where: 

• they satisfy the legislative definition of an on-site system
• no applicable Acceptable Solution or Verification Method exists
• meet the performance requirements of the applicable Building Code clause. 

 An on-site system means a system for the independent management of water that does not connect to a network utility operator (NUO) system. This includes systems for circulating, disposing of, storing, supplying, pumping or re-using water, as well as irrigation. 

Alternative solutions