ABLAQ Studios

Research / Environmental physics

Courtyard geometry
& direct sunlight.

How do courtyard proportions, wall height, and sun direction change the share of a floor exposed to direct sunlight?

Computational study 01Version 1.0Published 12 October 2026Open code & data

The question

Geometry changes exposure.

Courtyards bring open sky into buildings. The width and length of an opening, the height of its walls, and the sun’s position determine where direct light can reach the floor.

This study holds floor area at 100 m² and varies those four inputs. It uses a closed-form geometric calculation, checked against independent ray sampling. All 315 published configurations are computational results.

The quantity measured is the fraction of floor in direct sunlight at a chosen solar angle. It is a geometric exposure measure; it does not predict temperature, thermal comfort, or energy use.

Read the complete method

Interactive model

Change the geometry.
Follow the light.

Adjust the courtyard and sun position to see the calculation. Floor area remains 100 m²; all four walls share the same height.

Direct sunlight on a courtyard floor Top view of a 10 by 10 metre courtyard with 5 metre walls. At 45 degrees solar elevation and 45 degrees azimuth, 41.8 percent of the floor receives direct sunlight. PLAN VIEW · CONSTANT FLOOR AREA
10.00 m × 10.00 m · 100 m² floorDirect sunlightWall shadow

Floor in direct sunlight

41.8%

58.2% shaded

Calculated locally in your browser. A shared link includes the chosen inputs. Solar angles are user-defined, not calculated from a location or time. Model assumptions and limits.

Published results

Orientation matters.

The benchmark below compares three courtyard shapes at a fixed height and solar elevation. It stays fixed when you change the interactive model.

Sunlit floor fraction by sun directionAt 45 degrees solar elevation, the 4 to 1 rectangle falls from 75 percent sunlit along its length to zero along its width. The square is 50 percent sunlit at both ends and about 42 percent at 45 degrees.0%25%50%75%100%0°30°60°90°Sun direction from length axis1:1 plan2:1 plan4:1 plan
Directly sunlit floor fraction at 45° solar elevation, 5 m wall height and 100 m² floor area. The horizontal axis turns the sun from the length axis (0°) toward the width axis (90°). This plot is fixed; it does not change with the interactive model above.

A long courtyard responds more strongly to sun direction.

With 5 m walls and 45° solar elevation, a 5 × 20 m courtyard has 75% of its floor in direct sun when the sun is along its length. At 90°, the same floor is fully shaded.

These are instantaneous geometric comparisons. They do not establish which shape performs best over a day, season, or climate.

Sunlit floor · 100 m² · 5 m walls · 45° elevation
Shape0° sun45° sun90° sun
1:150.0%41.8%50.0%
2:164.6%37.5%29.3%
4:175.0%24.1%0.0%

Open research

Inspect. Reproduce.
Build on the work.

The release includes the analytical model, the full parameter sweep, and verification results. The Python implementation uses only the standard library.

Original study code and data are released under CC0. Attribution is appreciated; the ABLAQ identity is excluded from these reuse terms.

Suggested citation: ABLAQ Studios (2026). Courtyard geometry and direct sunlight. Version 1.0. ablaqstudios.com/research.

Reproduction instructions

Questions belong
in the open.

Found an issue or have a methodological question? Send the relevant configuration, result, or calculation.

Contact the research team