Solar & Daylight Data
Sun Path: Dundalk, Ireland
How to research sun path for a specific site in Dundalk — the controlling authority, source documents, and checks to run before you rely on a number.
On this page
Last updated August 31, 2026 · Location data from the [GeoNames IE dump](https://download.geonames.org/export/dump/IE.zip) (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 2964540). Regulatory starting point: [Department of Housing, Local Government and Heritage and the local building-control authority](https://www.gov.ie/en/department-of-housing-local-government-and-heritage/collections/building-standards/). 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 Dundalk at 54.0000, -6.4167, the declination-only solar-noon altitude is approximately 59.4° at the June solstice, 36.0° at an equinox and 12.6° 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 2964540 in administrative area L, at 54.0000, -6.4167; replace it with the surveyed parcel point before relying on the result. As a transparent geometry check, declination-only solar-noon altitude is about 59.4° at the June solstice, 36.0° at an equinox and 12.6° at the December solstice. Representative 21st-day geometry ranges from about 7.1 hours in December to 16.9 hours in June; 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.
Content and cited inputs reviewed by Harth team · Published 2026-08-26 · Updated 2026-08-31.
What must be verified for Dundalk?
Dundalk is represented here at approximately 54.0000, -6.4167 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 Dundalk site remain authoritative.
Dundalk monthly solar geometry check for sun path
| Representative date | Declination | Solar-noon altitude | Geometric daylight |
|---|---|---|---|
| 21 January | -20.14° | 15.9° | 8.0 h |
| 21 February | -11.23° | 24.8° | 9.9 h |
| 21 March | -0.40° | 35.6° | 11.9 h |
| 21 April | +11.58° | 47.6° | 14.2 h |
| 21 May | +20.14° | 56.1° | 16.0 h |
| 21 June | +23.45° | 59.4° | 16.9 h |
| 21 July | +20.44° | 56.4° | 16.1 h |
| 21 August | +11.75° | 47.8° | 14.2 h |
| 21 September | -0.20° | 35.8° | 12.0 h |
| 21 October | -11.75° | 24.2° | 9.8 h |
| 21 November | -20.44° | 15.6° | 7.9 h |
| 21 December | -23.45° | 12.6° | 7.1 h |


Month-by-month geometry interpretation
- 21 January: approximate solar-noon altitude 15.9° (zenith angle 74.1°) and 8.0 hours of geometric daylight. That is 0.8 hours longer than the preceding representative date in this annual sequence.
- 21 February: approximate solar-noon altitude 24.8° (zenith angle 65.2°) and 9.9 hours of geometric daylight. That is 1.9 hours longer than the preceding representative date in this annual sequence.
- 21 March: approximate solar-noon altitude 35.6° (zenith angle 54.4°) and 11.9 hours of geometric daylight. That is 2.0 hours longer than the preceding representative date in this annual sequence.
- 21 April: approximate solar-noon altitude 47.6° (zenith angle 42.4°) and 14.2 hours of geometric daylight. That is 2.3 hours longer than the preceding representative date in this annual sequence.
- 21 May: approximate solar-noon altitude 56.1° (zenith angle 33.9°) and 16.0 hours of geometric daylight. That is 1.9 hours longer than the preceding representative date in this annual sequence.
- 21 June: approximate solar-noon altitude 59.4° (zenith angle 30.6°) and 16.9 hours of geometric daylight. That is 0.8 hours longer than the preceding representative date in this annual sequence.
- 21 July: approximate solar-noon altitude 56.4° (zenith angle 33.6°) and 16.1 hours of geometric daylight. That is 0.8 hours shorter than the preceding representative date in this annual sequence.
- 21 August: approximate solar-noon altitude 47.8° (zenith angle 42.2°) and 14.2 hours of geometric daylight. That is 1.9 hours shorter than the preceding representative date in this annual sequence.
- 21 September: approximate solar-noon altitude 35.8° (zenith angle 54.2°) and 12.0 hours of geometric daylight. That is 2.3 hours shorter than the preceding representative date in this annual sequence.
- 21 October: approximate solar-noon altitude 24.2° (zenith angle 65.8°) and 9.8 hours of geometric daylight. That is 2.2 hours shorter than the preceding representative date in this annual sequence.
- 21 November: approximate solar-noon altitude 15.6° (zenith angle 74.4°) and 7.9 hours of geometric daylight. That is 1.9 hours shorter than the preceding representative date in this annual sequence.
- 21 December: approximate solar-noon altitude 12.6° (zenith angle 77.4°) and 7.1 hours of geometric daylight. That is 0.8 hours shorter than the preceding representative date in this annual sequence.
Harth calculation for latitude 54.0000°: 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: Drogheda, Ireland
- Sun Path: Navan, Ireland
- Sun Path: Swords, Ireland
- All solar & daylight data guidance for Ireland
- Climate Design Data: Dundalk, Ireland
- House Construction Cost Planning: Dundalk, Ireland
- Office Construction Cost Planning: Dundalk, Ireland
- Retail Construction Cost Planning: Dundalk, Ireland
Sources and method
Location data from the GeoNames IE dump (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 2964540). Regulatory starting point: Department of Housing, Local Government and Heritage and the local building-control authority. 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 Dundalk establish?
The sun path record for Dundalk establishes a reproducible discovery point at 54.0000, -6.4167 (GeoNames ID 2964540, administrative area L) and a Ireland 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 Dundalk?
For the sun path record in Dundalk, replace the 54.0000, -6.4167 city reference with the surveyed site or parcel, identify the competent local authority, and verify the current documents under Building Regulations and Technical Guidance Documents. Record the edition, retrieval date, units, assumptions and named checker before relying on the result.
Related pages
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Sun path for Droichead Nua, Ireland: solar-noon altitude 60.3° June, 36.8° equinox, 13.4° December; 7.3–16.7 h daylight; 12-month geometry table.
- Sun Path: Dubai, UAE
Sun path for Dubai, UAE: solar-noon altitude 88.4° June, 64.9° equinox, 41.5° December; 10.4–13.6 h daylight; 12-month geometry table.
- Sun Path: Dublin, Ireland
Sun path for Dublin, Ireland: solar-noon altitude 60.1° June, 36.7° equinox, 13.2° December; 7.2–16.8 h daylight; 12-month geometry table.
- Sun Path: Dunedin, New Zealand
Sun path for Dunedin, New Zealand: solar-noon altitude 20.7° June, 44.1° equinox, 67.6° December; 8.5–15.5 h daylight; 12-month geometry table.
- Sun Path: Durban, South Africa
Sun path for Durban, South Africa: solar-noon altitude 36.7° June, 60.1° equinox, 83.6° December; 10.1–13.9 h daylight; 12-month geometry table.
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Sun path for East London, South Africa: solar-noon altitude 33.5° June, 57.0° equinox, 80.4° December; 9.8–14.2 h daylight; 12-month geometry table.
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