Can I build a taller wall near the boundary now?
Yes. The side and rear building envelope has increased by 500 mm, from 3.5 m under the 2025 specifications to 4.0 m. The building envelope is formed by 45-degree planes projected from a height of 4 m above each side and rear boundary, with all height measurements taken from datum ground level. This requirement does not apply where solar building envelope requirements apply or where the specified exemptions in the Territory Plan apply.
The change in the solar building envelope requirements from 2025 to 2026 also affects maximum building height differently depending on whether the development is a single dwelling or multi-unit housing.
For single dwellings, the solar building envelope remains unchanged with the 31° projection angle, so there is no change to the height control.
For multi-unit housing, the projection angle increases from 31° to 45°, creating a larger buildable envelope and allowing greater design flexibility. However, the final maximum height is still determined by the interaction of the solar envelope, building envelope, height limits, setbacks, and other applicable planning controls.
Reference: Planning (Residential Zones) Technical Specifications 2026 (NI2026-303) – Planning (Residential Zones) Technical Specifications 2026
Short Answer
The side and rear building envelope has increased by 500 mm, from 3.5 m to 4.0 m, with a 45° plane projected from each side and rear boundary (measured from datum ground level). This does not apply where solar building envelope requirements or specified exemptions apply. For single dwellings, the solar envelope remains unchanged at 31°, so there is no change to height control. For multi-unit housing, the solar envelope changes from 31° to 45°, providing a larger buildable envelope and greater design flexibility. The final height remains subject to all applicable controls, including building envelopes, height limits, setbacks, and solar requirements.
Detailed Explanation
The side and rear building envelope requirement has increased by 500 mm, changing from 3.5 m under the 2025 specifications to 4.0 m under the 2026 specifications. The building envelope is now formed by 45° planes projected from a height of 4.0 m above each side and rear boundary, with all height measurements taken from datum ground level. This provides additional flexibility for building design by allowing a greater building envelope compared with the previous requirement. This building envelope requirement does not apply where solar building envelope requirements apply to the relevant side or rear boundary, or where specific exemptions under the Territory Plan apply, such as certain compact blocks, buildings over three storeys in RZ5, or development required to be built to a boundary under a District Policy or specification. Encroachments outside the building envelope remain limited to permitted items such as flues, chimneys, antennae, aerials, cooling appliances, and heating appliances. The 2026 solar building envelope changes also affect development potential depending on the type of housing. For single dwellings, the solar envelope remains unchanged, with the projection angle continuing at 31°, meaning there is no change to the solar height control. For multi-unit housing, the projection angle changes from 31° to 45°, creating a larger buildable envelope and allowing greater design flexibility while continuing to protect solar access. The maximum achievable building height is therefore determined by the combined effect of the building envelope, solar building envelope, height limits, setbacks, and other applicable Territory Plan requirements.
No minimum block size does not remove the need for planning assessment.
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