Has the building height limit changed for our zone?
The ACT building height rules have changed significantly between the 2025 and 2026 planning provisions.
The 2025 rules mainly controlled building height by the maximum number of storeys, with some zones using a maximum height in metres. The 2026 rules move to a height-based system measured in metres above datum ground level and introduce different height limits depending on whether the development is single dwelling housing or multi-unit housing.
This change provides more flexibility for higher-density housing while maintaining lower height limits for individual houses.
Comparison of Building Height Rules
| Residential Zone | 2025 Rule | 2026 Rule |
|---|---|---|
| RZ1 | Maximum 8.5m above datum ground level | Maximum 8.5m above datum ground level |
| RZ2 | Maximum 8.5m above datum ground level | Single dwelling housing: 8.5m Multi-unit housing: 10.5m |
| RZ3 | Maximum 2 storeys | Single dwelling housing: 10.5m Multi-unit housing: 14m |
| RZ4 | Maximum 3 storeys | Single dwelling housing: 10.5m Multi-unit housing: 21m |
| RZ5 | Maximum: • 3 storeys near RZ1/RZ2/RZ3 boundaries • 3 storeys near CFZ, PRZ1 or PRZ2 boundaries • 4 storeys near RZ4 boundaries • 6 storeys in other locations |
Single dwelling housing: 10.5m Multi-unit housing: 24.5m |
Reference: Reference: Planning (Residential Zones) Technical Specifications 2026 (NI2026-303), Assessment Outcome 14.1- Planning (Residential Zones) Technical Specifications 2026
Short Answer
The main change is that the 2025 rules controlled buildings mainly by storeys, while the 2026 rules control buildings by maximum height in metres and provide different limits for single dwellings and multi-unit housing. Zone 2025 Rule 2026 Rule RZ1 8.5m 8.5m RZ2 8.5m Single dwelling: 8.5m Multi-unit: 10.5m RZ3 2 storeys Single dwelling: 10.5m Multi-unit: 14m RZ4 3 storeys Single dwelling: 10.5m Multi-unit: 21m RZ5 3–6 storeys depending on location Single dwelling: 10.5m Multi-unit: 24.5m In summary: The 2026 rules replace simple storey limits with measurable height limits. Multi-unit developments generally receive higher height allowances. The changes provide more flexibility for medium and higher-density housing while maintaining lower heights for single dwellings.
Detailed Explanation
Yes.
1. Storey limits have been replaced with height limits
Under the 2025 rules, compliance was mainly determined by the number of storeys.
For example:
- RZ3 → maximum 2 storeys
- RZ4 → maximum 3 storeys
Under the 2026 rules, the assessment focuses on the actual building height.
Example:
A three-storey townhouse development in RZ3 may now be possible if it remains within the maximum height limit of:
- 10.5m for single dwelling housing
- 14m for multi-unit housing
The number of storeys alone is no longer the only determining factor.
2. Multi-unit housing receives greater height allowances
The 2026 rules introduce separate standards for different housing types.
Example:
RZ2
| Development type | Maximum height |
|---|---|
| Single dwelling house | 8.5m |
| Multi-unit housing | 10.5m |
This recognises that multi-unit housing generally requires additional height to accommodate efficient layouts, shared spaces and increased housing supply.
3. Higher-density zones receive increased development capacity
The largest changes occur in RZ3, RZ4 and RZ5.
Example:
RZ4
2025:
- Maximum 3 storeys
2026:
- Single dwelling housing: 10.5m
- Multi-unit housing: 21m
This represents a significant increase in potential building scale for appropriate multi-unit developments.
4. RZ5 changes from location-based controls to development-based controls
Previously, RZ5 height depended partly on what surrounded the site.
For example:
- Near lower-density residential areas → lower height
- In other locations → higher height
The 2026 rules simplify this approach by applying a clear maximum height based on the type of development.
No minimum block size does not remove the need for planning assessment.
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