G-03 Glossary term
Building coverage
The percentage of your site covered by buildings when viewed from above.
At a glance
Building coverage at a glance
- What counts
- Every existing and proposed building footprint counted by the planning definition
- Calculation
- Total counted building footprint ÷ net site area × 100
- Residential-zone limit
- No more than 50% under the NES-DMRU
- What passing means
- One planning check, not permission for the whole project
Which coverage limit applies?
In a residential zone, the NES-DMRU limits total building coverage to 50% of the net site area.
In a rural, mixed-use or Māori-purpose zone, use the building-coverage standard in the district plan. A district plan can set a more lenient standard. Check the current plan before relying on it, and record the rule used in the assessment.
What counts as a building footprint?
Picture the property from directly above. Building coverage measures the ground occupied by counted buildings, not the space inside them. A two-storey house can have twice as much internal floor area without occupying twice as much ground.
The definition also counts parts of a building that extend beyond the ground-floor limits and overhang the ground. Use the final building footprint, not the internal floor area.
Which three figures do you need?
- 01/
Net site area
Confirm the area used by the planning definition. It can differ from the total on a property record because specified access areas and land subject to certain designations are excluded.
- 02/
Existing building footprint
Measure every existing building the definition counts. The total can include a garage, sleepout or other structure as well as the main house.
- 03/
Proposed building footprint
Use the final roof and wall dimensions. Ask the designer to show the footprint used in the calculation on the site plan.
Worked example: Anika’s 600 m² site
| Measure | Area | What it means |
|---|---|---|
| Net site area | 600 m² | The area used in the calculation |
| Residential limit | 300 m² | 50% of the net site area |
| Existing buildings | 205 m² | House, garage and other counted footprints |
| Proposed granny flat | 70 m² | Proposed footprint |
| New total | 275 m² | 45.8% building coverage |
What could change the result?
A covered porch, a larger roof overhang or an existing garage missing from the site plan would change Anika’s calculation. A few square metres can decide whether a tight site stays below its limit.
Going over the limit does not always end the project. Anika could revise the footprint, remove an unused building or check whether a more lenient district-plan standard applies. Each option changes the design or the rule being relied on, so it must be checked again.
What is building coverage often confused with?
| Term | What it measures |
|---|---|
| Impervious area | Surfaces that do not absorb rainwater, including some paving. |
| Floor area | Space inside a building. |
| Yards or setbacks | The required distance between a building and a boundary. |
| Outdoor living space | Usable outdoor area required by some planning rules. |