Solar & Daylight Data
Solar Shading Design: Bengaluru, India
How to research solar shading design for a specific site in Bengaluru — the controlling authority, source documents, and checks to run before you rely on a number.
On this page
Last updated September 2, 2026 · Location data from the [GeoNames IN dump](https://download.geonames.org/export/dump/IN.zip) (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 1277333). Regulatory starting point: [Bureau of Indian Standards and the applicable state or urban local body](https://www.services.bis.gov.in/php/BIS_2.0/bisconnect/knowyourstandards/Indian_standards/isdetails/). 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. Project-date refinement reference: [NREL Solar Position Algorithm](https://midcdmz.nrel.gov/spa/).
Direct answer
For Bengaluru at 12.9719, 77.5937, the declination-only solar-noon altitude is approximately 79.5° at the June solstice, 77.0° at an equinox and 53.6° 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 1277333 in administrative area 19, at 12.9719, 77.5937; replace it with the surveyed parcel point before relying on the result. As a transparent geometry check, declination-only solar-noon altitude is about 79.5° at the June solstice, 77.0° at an equinox and 53.6° at the December solstice. Representative 21st-day geometry ranges from about 11.2 hours in December to 12.8 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 solar shading design record.
Content and cited inputs reviewed by Harth team · Published 2026-08-26 · Updated 2026-09-02.
What must be verified for Bengaluru?
Bengaluru is represented here at approximately 12.9719, 77.5937 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 solar shading design 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 shading-workflow page is a project-starting worksheet, not a design value or approval. The controlling authority and qualified professionals for the Bengaluru site remain authoritative.
Bengaluru horizontal-overhang screening worksheet
| Representative date | 09:00 altitude / P:H | Solar noon altitude / P:H | 15:00 altitude / P:H |
|---|---|---|---|
| 21 January | 34.73° / 1.443 | 56.89° / 0.652 | 34.73° / 1.443 |
| 21 February | 39.21° / 1.226 | 65.80° / 0.449 | 39.21° / 1.226 |
| 21 March | 43.43° / 1.056 | 76.62° / 0.238 | 43.43° / 1.056 |
| 21 April | 46.06° / 0.964 | 88.61° / 0.024 | 46.06° / 0.964 |
| 21 May | 46.40° / 0.952 | 82.83° / 0.126 | 46.40° / 0.952 |
| 21 June | 46.18° / 0.960 | 79.52° / 0.185 | 46.18° / 0.960 |
| 21 July | 46.39° / 0.953 | 82.53° / 0.131 | 46.39° / 0.953 |
| 21 August | 46.08° / 0.963 | 88.78° / 0.021 | 46.08° / 0.963 |
| 21 September | 43.49° / 1.054 | 76.83° / 0.234 | 43.49° / 1.054 |
| 21 October | 38.97° / 1.236 | 65.27° / 0.460 | 38.97° / 1.236 |
| 21 November | 34.56° / 1.452 | 56.59° / 0.660 | 34.56° / 1.452 |
| 21 December | 32.88° / 1.547 | 53.58° / 0.738 | 32.88° / 1.547 |


Bengaluru overhang sizing hand check
P:H is projection depth divided by the vertical facade distance to shade, calculated as 1 / tan(solar altitude). For a 1.20 m vertical target, multiply the table ratio by 1.20 m. The 09:00 and 15:00 columns use apparent solar time and show the solar-profile-plane ratio; they do not resolve facade azimuth, horizontal shadow displacement or a side-fin geometry.
The Bengaluru worksheet uses latitude 12.9719° and records longitude 77.5937°. A project study must replace the reference point, use the actual facade normal and obstruction mask, convert to civil time, test the full occupied period and account for diffuse sky, glazing and thermal performance. Refine solar positions with the NREL SPA.
Where can you explore related guidance?
- Explore all solar data guidance
- Sun Path: Bengaluru, India
- Solar Altitude & Azimuth: Bengaluru, India
- Daylight & Orientation: Bengaluru, India
- Solar Shading Design: Kallakurichi, India
- All solar & daylight data guidance for India
- Climate Design Data: Bengaluru, India
- House Construction Cost Planning: Bengaluru, India
- Office Construction Cost Planning: Bengaluru, India
- Retail Construction Cost Planning: Bengaluru, India
Sources and method
Location data from the GeoNames IN dump (CC BY 4.0, snapshot 2026-08-31, GeoNames ID 1277333). Regulatory starting point: Bureau of Indian Standards and the applicable state or urban local body. 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. Project-date refinement reference: NREL Solar Position Algorithm.
Source links
Frequently asked questions
What does the solar shading design record for Bengaluru establish?
The solar shading design record for Bengaluru establishes a reproducible discovery point at 12.9719, 77.5937 (GeoNames ID 1277333, administrative area 19) and a India source path. It does not establish a final project value, approval or parcel decision.
What must be replaced before using this solar shading design workflow for a project in Bengaluru?
For the solar shading design record in Bengaluru, replace the 12.9719, 77.5937 city reference with the surveyed site or parcel, identify the competent local authority, and verify the current documents under National Building Code of India plus state and urban-local-body rules. Record the edition, retrieval date, units, assumptions and named checker before relying on the result.
Related pages
- Solar Shading Design: Ballarat, Australia
Solar shading design for Ballarat, Australia: horizontal-overhang P:H ratios at 09:00, noon and 15:00 by month; June noon altitude 29.0°; sizing hand check.
- Solar Shading Design: Barrie, Canada
Solar shading design for Barrie, Canada: horizontal-overhang P:H ratios at 09:00, noon and 15:00 by month; June noon altitude 69.0°; sizing hand check.
- Solar Shading Design: Bendigo, Australia
Solar shading design for Bendigo, Australia: horizontal-overhang P:H ratios at 09:00, noon and 15:00 by month; June noon altitude 29.8°; sizing hand check.
- Solar Shading Design: Bhopal, India
Solar shading design for Bhopal, India: horizontal-overhang P:H ratios at 09:00, noon and 15:00 by month; June noon altitude 89.8°; sizing hand check.
- Solar Shading Design: Blue Mountains, Australia
Shading design for Blue Mountains, Australia: overhang P:H ratios at 09:00, noon and 15:00 by month; June noon altitude 32.9°.
- Solar Shading Design: Brisbane, Australia
Solar shading for Brisbane, Australia: warm months September to May, overhang P:H by month, and how much sun overhangs and fins block on each facade.
Design for your site's sun. Render it on your 3D model.