Designing with daylight
A building envelope is not just an external skin alone…Its materials, geometry, and design guide daylight, shaping comfort, mood, and energy efficiency.
Building envelopes are not just external skins. Lighting Designer Manju Dileep explains how materiality, geometry, and design of building envelopes influence lighting inside a building.
How do materials chosen for building envelopes influence natural lighting inside a building?
The materials you choose for a building envelope basically tell daylight how to behave once it arrives. It governs the play of light within the space, deciding whether it should feel bright and airy, diffused and moody, or calm & soothing. They can act as dynamic filters that set the tone for space. For example, clear glass allows a huge amount of direct light, but can cause glare and high contrast when not designed thoughtfully. Similarly, translucent materials like polycarbonate panels can be an appropriate choice because they evenly spread light, reducing glare and diffusing daylight. Light reflected inside a building is also defined by the surface reflectance, texture, and geometry of the materials within the envelope.
What are the best ways to integrate artificial lighting with natural lighting to maximise energy efficiency?
The most effective lighting strategies start with daylight. Intelligent Energy Management Systems use daylight harvesting to sense natural light levels and automatically dim artificial lighting, maintaining visual comfort while reducing energy use. Design plays an equally important role. Light shelves help push daylight deeper into interiors, while high-reflectance ceilings and walls amplify its reach. When paired with adaptive technologies like electrochromic glass, which controls glare without blocking light, the result is a seamless balance between natural and artificial illumination, delivering both efficiency and comfort.
How do roofs and floors influence the visual comfort of occupants in buildings? And, why is it important to design for optimal sunlight exposure and glare in a hot climate?
Visual comfort begins at the building’s edges, where roofs filter daylight and floors reflect or absorb light to shape the interior experience. Roofs can act as light collectors – skylight windows on roofs can collect natural light and pass it into deep interiors where windows cannot reach. The roof shape can also be adjusted to affect the amount of daylight reaching the interiors. Floors control brightness distribution and glare reduction. Light-coloured floors (with a recommended reflectance of around 20%) bounce light further into a room, even though they have less impact than ceilings/walls. And, matte and low-sheen finishes reduce glare and create a cosy, natural appearance. It is preferable to avoid high-gloss floors, as they can cause “veiling reflections” that result in visual discomfort.
How can building envelopes be designed to reduce light pollution by managing daylighting and shading?
Thoughtful building envelope design plays a key role in reducing light pollution. Using low-reflectance façade materials helps limit interior light spill into the surroundings and night sky, while low-emissivity glazing and coatings control light trespass through windows and glazed doors. Shading elements such as louvres, vertical fins, and kinetic facades further direct light where it is needed, and adaptive solutions like electrochromic glass can shift to darker tints at night, minimising unnecessary light leakage without compromising daytime performance.