Designers: step-by-step guide to plumbing and drainlaying self-certification

Step 1: Designer determines whether self-certification may be suitable

The designer will discuss the project with the owner and project team.

Together they will consider whether the proposed plumbing and drainlaying will qualify for self-certification and whether to use this pathway.

Step 2: The work is designed

The designer prepares plans and specifications that:

• comply with the Building Code
• clearly identify the proposed self-certifiable plumbing and drainlaying and what will instead go through the building consent authority (BCA) inspection process
• specify applicable compliance pathways – only plumbing and drainlaying designed to an Acceptable Solution or Verification Method is eligible, unless it’s a qualifying on-site system.

The designer should clearly show which work will be self-certified and which work will be inspected by a BCA.

Step 3: Designer coordinates with practitioners

The designer will work with:

• endorsed plumbers
• endorsed drainlayers
• engineers
• other designers

to ensure the proposed scope of self-certification is understood.

Step 4: Designer supports the building consent application

In the building consent application, the designer must:

• describe the work proposed to be self-certified and how it’s intended to be carried out (whether the endorsed plumber or drainlayer will carry out, assist with, or supervise the plumbing and drainlaying)
• provide the name of the endorsed plumber or drainlayer, if known
• provide plans and specifications that will meet the requirements of the Building Code.

Step 5: Designer responds to requests for information

If requested by the BCA, the designer should:

• clarify design details
• provide additional information, whether it’s about proposed self-certified work or otherwise
• explain proposed compliance pathways.

Step 6: Design changes are managed

If changes occur during construction, the designer:

• assesses whether consented drawings need updating
• supports minor variations or building consent amendment applications where required.

Step 7: Designer updates documentation

Where changes are approved, the designer:

• revises plans and specifications
• clearly identifies any changes affecting self-certification.

Self-certification is optional. If plumbing and drainlaying work does not require a building consent, it is not eligible for the scheme. This is because self-certification removes the need for BCA inspections for eligible work listed on the building consent as self-certifiable.