How to identify defects

Last updated: 21 March 2016

Homeowners and builders can use our Guide to tolerances, materials and workmanship as one way to help determine an acceptable level of finish or workmanship at the completion of a building project.

The guide outlines acceptable levels of workmanship in standard domestic construction under normal conditions. It is targeted at new residential building work. Acceptable levels of workmanship in renovations may differ, as the work is a mixture of old and new which may require more compromise.

Renovations differ to new builds

A building renovation or alteration differs to a new build, requiring careful planning to cope with unknown factors

Renovations differ to new builds

This guide is concerned with defects that a contractor would be required to remedy if notified within one year of completing the building work. It supports new consumer protection measures that came into law in January 2015.

The guide can help align expectations of the end product, as it covers design choices and chosen materials, finishes and costs. You can also refer to it at the beginning of a project to ensure everyone has the same expectations, and include it as part of a contract.

However, the guide is not a mandatory set of quality standards. Contractors and clients can mutually agree to use their own standards for tolerances, materials and workmanship. Either way, they should agree in writing and preferably within their contract.

Establishing acceptable tolerances

If a building owner believes they have identified a defect, they should immediately talk to their building contractor about the issue and how to resolve it.

The process for determining if it is a ‘defect’ should refer to (in order):

  1. the contract, drawings, specifications and schedule of quantities if relevant
  2. the building consent and supporting documentation supplied to the Council
  3. manufacturers’ specifications and installation instructions
  4. any building contractors’ defect tolerance schedule where its use was agreed to in the contract
  5. any relevant NZ Standard
  6. our guide.

Where an issue is raised that is not covered by any of these information sources, you may need professional advice to establish if the issue is a defect and how it should be rectified.

If the defect is suspected or known to be a Building Code compliance issue, the next step should be to contact the relevant council that issued the building consent or code compliance certificate.

It is common for variations (both minor and major) to occur during a construction project. It is important the owner’s instructions or agreement to variations proposed by the designer or building contractor are recorded to avoid differences in expectations and potential disputes.

If you think work has been varied without your knowledge you need to find out from the main contractor. They will also be able to tell you about any implications of the variation (for example, increased time or cost, and altered finish).

Where an owner requires a building contractor to carry out work the building contractor knows will result in a less than satisfactory finish or outcome for one or both parties, this should be put in writing to the owner before starting the work.

If you are dissatisfied with something that is installed to a specification and to a reasonable standard (as outlined in this guide), it may not be a defect. For example, an owner cannot expect a level five plaster finish if the specification called for a level four plaster finish.

Guide to tolerances

In brief, the guide explains that a defect includes:

  • anything that does not comply with the Building Code
  • variations from consented drawings that have not been agreed
  • failure to meet specifications agreed in the contract
  • product failure earlier than anticipated
  • failure to achieve acceptable industry levels of quality or performance on items not covered by the first four bullet points (as outlined in the guide)

The building contractor cannot be held liable for an event they or their subcontractors weren't involved in, including damage:

  • that is not within human control (for example, natural disaster)
  • done by a person outside their control
  • resulting from a failure to undertake normal maintenance (by the building owner)
  • resulting from a failure to carry out repairs as soon as practical after the defect became apparent.

This guide has been developed in cooperation with an advisory group from the construction industry and a consumer representative. It draws on existing industry norms for workmanship set out in New Zealand Standards and trade publications.

Resolving problems includes information about problems and resolution options. 

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: