Solar & Daylight Data
Sun Path: Porirua, New Zealand
How to research sun path for a specific site in Porirua — the controlling authority, source documents, and checks to run before you rely on a number.
Last updated August 31, 2026 · Location data from the [GeoNames NZ dump](https://download.geonames.org/export/dump/NZ.zip) (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 2184397). Regulatory starting point: [Ministry of Business, Innovation and Employment and the local council](https://www.building.govt.nz/building-code-compliance). Figures are illustrative — verify against the current locally adopted edition for the site. Solar-method context: [NOAA Solar Calculation Details](https://gml.noaa.gov/grad/solcalc/calcdetails.html); the Harth monthly table uses a simpler declination and geometric-daylight approximation whose stated limitations must be retained.
Direct answer
For Porirua at -41.1333, 174.8500, the declination-only solar-noon altitude is approximately 25.4° at the June solstice, 48.9° at an equinox and 72.3° at the December solstice. Refine these geometry checks with the project date, civil time, facade azimuth, terrain and local horizon. The reproducible location record is GeoNames ID 2184397 in administrative area G2, at -41.1333, 174.8500; replace it with the surveyed parcel point before relying on the result. As a transparent geometry check, declination-only solar-noon altitude is about 25.4° at the June solstice, 48.9° at an equinox and 72.3° at the December solstice. Representative 21st-day geometry ranges from about 9.0 hours in June to 15.0 hours in December; this excludes atmospheric refraction, terrain and obstruction effects. The cited national authority is a discovery starting point; current local documents and a named qualified reviewer control project use of this sun path record.
Prepared by Harth · Prepared from the cited location and country sources; local project inputs remain unreviewed · Published 2026-08-26 · Updated 2026-08-31.
What must be verified for Porirua?
Porirua is represented here at approximately -41.1333, 174.8500 for discovery and workflow planning. A project address, parcel, elevation, exposure, authority, and submission date must replace that city-centre reference before design use.
How should sun path be established?
- Fix the surveyed site and local time basis.
- Select an authoritative weather source or a named solar-position algorithm.
- Record period, percentile or scenario and units.
- Test sensitivity to elevation, exposure, urban form and horizon.
- Save the source file, retrieval date and checker in the model record.
| Input | Project-specific evidence | QA question |
|---|---|---|
| Site | surveyed coordinates, elevation and horizon | Does the point represent the building? |
| Weather/solar method | named dataset, algorithm, period and time basis | Are station, time zone and units explicit? |
| Design scenario | current and future scenario agreed by the team | Is an average being mistaken for an extreme? |
| Compliance | adopted local document and edition | Was applicability confirmed with the authority? |
What are the limits of this worksheet?
This sun-path-workflow page is a project-starting worksheet, not a design value or approval. The controlling authority and qualified professionals for the Porirua site remain authoritative.
Which related searches does this primary location record cover?
This primary route consolidates the location evidence needed for Sun Path, Solar Altitude & Azimuth, Solar Shading Design, Daylight & Orientation. A narrower route should be released only when it adds a materially different official source, calculation, process, threshold or worked example.
Porirua monthly solar geometry check for sun path
| Representative date | Declination | Solar-noon altitude | Geometric daylight |
|---|---|---|---|
| 21 January | -20.14° | 69.0° | 14.5 h |
| 21 February | -11.23° | 60.1° | 13.3 h |
| 21 March | -0.40° | 49.3° | 12.0 h |
| 21 April | +11.58° | 37.3° | 10.6 h |
| 21 May | +20.14° | 28.7° | 9.5 h |
| 21 June | +23.45° | 25.4° | 9.0 h |
| 21 July | +20.44° | 28.4° | 9.5 h |
| 21 August | +11.75° | 37.1° | 10.6 h |
| 21 September | -0.20° | 49.1° | 12.0 h |
| 21 October | -11.75° | 60.6° | 13.4 h |
| 21 November | -20.44° | 69.3° | 14.5 h |
| 21 December | -23.45° | 72.3° | 15.0 h |
Month-by-month geometry interpretation
- 21 January: approximate solar-noon altitude 69.0° (zenith angle 21.0°) and 14.5 hours of geometric daylight. That is 0.5 hours shorter than the preceding representative date in this annual sequence.
- 21 February: approximate solar-noon altitude 60.1° (zenith angle 29.9°) and 13.3 hours of geometric daylight. That is 1.2 hours shorter than the preceding representative date in this annual sequence.
- 21 March: approximate solar-noon altitude 49.3° (zenith angle 40.7°) and 12.0 hours of geometric daylight. That is 1.3 hours shorter than the preceding representative date in this annual sequence.
- 21 April: approximate solar-noon altitude 37.3° (zenith angle 52.7°) and 10.6 hours of geometric daylight. That is 1.4 hours shorter than the preceding representative date in this annual sequence.
- 21 May: approximate solar-noon altitude 28.7° (zenith angle 61.3°) and 9.5 hours of geometric daylight. That is 1.1 hours shorter than the preceding representative date in this annual sequence.
- 21 June: approximate solar-noon altitude 25.4° (zenith angle 64.6°) and 9.0 hours of geometric daylight. That is 0.5 hours shorter than the preceding representative date in this annual sequence.
- 21 July: approximate solar-noon altitude 28.4° (zenith angle 61.6°) and 9.5 hours of geometric daylight. That is 0.4 hours longer than the preceding representative date in this annual sequence.
- 21 August: approximate solar-noon altitude 37.1° (zenith angle 52.9°) and 10.6 hours of geometric daylight. That is 1.1 hours longer than the preceding representative date in this annual sequence.
- 21 September: approximate solar-noon altitude 49.1° (zenith angle 40.9°) and 12.0 hours of geometric daylight. That is 1.4 hours longer than the preceding representative date in this annual sequence.
- 21 October: approximate solar-noon altitude 60.6° (zenith angle 29.4°) and 13.4 hours of geometric daylight. That is 1.4 hours longer than the preceding representative date in this annual sequence.
- 21 November: approximate solar-noon altitude 69.3° (zenith angle 20.7°) and 14.5 hours of geometric daylight. That is 1.1 hours longer than the preceding representative date in this annual sequence.
- 21 December: approximate solar-noon altitude 72.3° (zenith angle 17.7°) and 15.0 hours of geometric daylight. That is 0.4 hours longer than the preceding representative date in this annual sequence.
Harth calculation for latitude -41.1333°: Cooper declination approximation, 90° - |latitude - declination| at solar noon, and centre-to-centre sunrise hour angle. See NOAA's solar calculation details for fuller method context. This screening table excludes equation-of-time/civil-time conversion, atmospheric refraction, terrain, facade azimuth and obstructions; it is not an hourly shading result.
Where can you explore related guidance?
- Explore all solar data guidance
- Sun Path: Wellington, New Zealand
- Sun Path: Paraparaumu, New Zealand
- Sun Path: Levin, New Zealand
- Sun Path: Blenheim, New Zealand
Sources and method
Location data from the GeoNames NZ dump (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 2184397). Regulatory starting point: Ministry of Business, Innovation and Employment and the local council. Figures are illustrative — verify against the current locally adopted edition for the site. Solar-method context: NOAA Solar Calculation Details; the Harth monthly table uses a simpler declination and geometric-daylight approximation whose stated limitations must be retained.
Source links
Frequently asked questions
What does the sun path record for Porirua establish?
The sun path record for Porirua establishes a reproducible discovery point at -41.1333, 174.8500 (GeoNames ID 2184397, administrative area G2) and a New Zealand source path. It does not establish a final project value, approval or parcel decision.
What must be replaced before using this sun path workflow for a project in Porirua?
For the sun path record in Porirua, replace the -41.1333, 174.8500 city reference with the surveyed site or parcel, identify the competent local authority, and verify the current documents under New Zealand Building Code, Acceptable Solutions, and Verification Methods. Record the edition, retrieval date, units, assumptions and named checker before relying on the result.
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