Why is Daylight Important in Design?
Daylight:
- Improves indoor comfort and well-being
- Access to natural light supports health and productivity
- Reduces energy demand
- Less reliance on artificial lighting
- Enhances spatial quality
- Better perception of space, depth, and materials
- Supports building performance
- Contributes to sustainability and energy efficiency (e.g. Leed Certification)-
- Required by regulations
- Minimum daylight levels often defined in building codes
Daylight Analysis in Forma Site Design
Daylight analysis measures how much sky light reaches façades, expressed as a percentage. This is known as the Vertical Sky Component, or VSC. It represents the potential for daylight to enter a building through windows.
Forma Site Design uses this VSC to analyze and provide you with insights regarding the daylight potential of the buildings you design on your site. The analysis is based on a standardized overcast sky model, meaning it does not include direct sunlight. It accounts for shading from surrounding geometry but does not consider interior layouts or materials.
- What the Results Represent
- Amount of light reaching façades from the sky, expressed as a percentage (Sky Component / VSC)
- Indicates how much light could enter through a window at those points
- Useful for identifying façade areas with higher daylight access during early-stage design
- Detailed compliance verification should be performed in dedicated daylight simulation tools
- Key Concepts
- Based on a standard overcast sky model (no direct sun, fixed conditions 21st of September)
- Includes shading from buildings, terrain, and vegetation
- Does not account for window sizes, materials, interior layout or room functions
- Key Difference from Sun Hours
- Sun Hours = direct sunlight (time-based)
- Daylight = sky exposure (geometry-based)
Workflow — Running a Daylight Analysis
- Open a proposal.
- In the right panel, go to Analyze → Daylight Analysis.
- In the analysis area menu at the top of the right panel, select one or more site limits or zones.
- Click Run analysis to start.
- Repeat this process for each proposal you want to compare.
Exploring and Interpreting the Analysis Results
Example: Comparing Building Facades Visually
Example: Comparing Daylighting Statistics
Additional Resources
To learn more about the features of Daylight Potential analysis and the feedback available, read this articles:
- Introduction to Daylight Potential Analysis
- The Technology Behind the Daylight Potential Analysis