Retrofitting insulation to external walls

Cover page of the Retrofitting insulation to the external walls guidance.

If you're a building consent authority (BCA), this guidance will help you manage building consent applications for retrofitting wall insulation. If you're a designer or installer, you may find this guidance useful for understanding the requirements.

  • Published on 31 March 2025
  • Of interest to Building consent authorities, Designers, Insulation installers,
  • ISBN: 978-1-991316-34-9 (Online)

Version control

1st edition - August 2011

2nd edition - March 2025

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: