Big Changes Ahead: What New Granny-Flat Rules Mean for DIY Builders

New Zealand is entering a new era for backyard housing. From early 2026, homeowners can build small standalone granny flats—up to about 70 m²—without needing a building consent, provided certain conditions are met.

This change aims to make it easier for families to add housing options like tiny homes, sleepouts, and self-contained cabins.

However, it’s not a free-for-all. Projects still need to meet the Building Code, follow simple design rules, and often involve licensed professionals.  Councils may also require a Project Information Memorandum (PIM), site checks, or notifications before and after construction.

For DIY builders, this is huge. Flatpack cabins already align with many of these requirements because they’re designed to be structurally sound, building act compliant, and easy to supervise professionally.

A PS1 from an engineer may still be required depending on foundation type, site conditions, or customisations. Planning early ensures your project stays compliant and insurable.

The takeaway? Building a granny flat or self-contained cabin is becoming simpler—but smart preparation still matters.

If you’ve been waiting for the “right time,” this policy shift might be it. Read more about the changes in this Stuff Article.