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What's the deal with building regulations and outbuildings?

2 min read
Oct '25 • by Heather

Quick summary

Building regulations usually apply if your outbuilding is over 15 square metres or you plan to sleep in it, regardless of cost, and generally need approval from your council’s building control. Small structures under 15 sqm or below 30 sqm without sleeping space often don’t need them. Outbuildings must be at least one metre from boundaries and built from non-combustible materials.

It’s unlikely that in day to day conversation you’ll hear the phrase ‘building regulations’ or ‘outbuildings’ come up, not unless you hang around with city planners and architects. But both are important terms to know, if you’re looking at adding another structure to your property.

First things first, an outbuilding is classed as any of the following…

  • A garage or carport
  • Summerhouse or shed
  • Greenhouse
  • Animal dwellings, such as for birds or bees
  • Outdoor saunas

...and more!

Basically, any outside structure that’s permanent would be classed as an outbuilding. So what do they have to do with building regulations?

How much does an architect charge?