From November 2023 the Building Code Acceptable Solutions for Protection from Fire (C/AS1 and C/AS2) will be amended to make interconnected smoke alarms the minimum fire safety system for new built homes and substantial renovations, citing NZS 4514:2021 – Interconnected smoke alarms for Houses.

Essentially any new build or renovated homes will need all their smoke alarms interconnected (if more than one) and installed in all locations (not just 3m of bedrooms).

Key changes:

  1. If there is more than one smoke detector in the home, they will all need to be interconnected (to all sound at same time). They need to either interconnect via 240V, Low Voltage (security alarms) or via wireless RF.
  2. Smoke detectors need to be now installed into ALL Bedrooms, Living Spaces, Hallways and Landings within the home.
  3. Where the Kitchen is not ‘open plan’ to a Living Room with a smoke detector, then the isolated Kitchen area needs to have a heat or smoke detector. Garages are optional.
  4. Smoke detectors need to be within 10m of each other in any direction
  5. All smoke detectors/systems must have a Hush Button and Test Button
  6. There must be an audible signal between 75dB – 110dB in all Bedrooms, Living Spaces, Hallways and Landings
  7. Low voltage smoke detectors must be installed with a 0.5mm stranded cable
  8. Each smoke detector system should be tested monthly, and should be inspected & cleaned six-monthly

Example: (image credit: )

NZS example floorplan for smoke alarms

The Building System Performance branch of MBIE has sponsored access to view and print a single downloadable PDF copy of this standard at no charge. Standards New Zealand also offers this standard to be purchased as Hard Copy or Online Library subscription.  Visit to download or purchase a copy of NZ Standard 4515:2021 Interconnected smoke alarms for houses.

If you are interested in upgrading to interconnected smoke alarms to keep your family safe. talk to one of our friendly consultants today. Phone 09 377 3778 or email

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