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Daylight & sunlight


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Sustainable design must optimize daylighting and also control when and how sunlight enters the building. With careful design, daylighting can be used for task lighting during most of the day for much of the year. Utilizing daylighting and so avoiding artificial lighting is also an important way to reduce total energy costs, especially in non-residential buildings.

More than that, though, natural light can be used creatively to provide visually stimulating indoor environments. The variability in natural light colour, shadows, brightness contrasts, sun angle over the day and across the seasons should be part of a designer's palette. Daylight and controlled pools of sunlight both create visual interest and buoy up occupants' health and emotional well-being, comfort, and productivity which tends to increase occupant satisfaction with the building. While high levels of daylight are preferable, simply having natural light in interiors has positive effects.

Furthermore, emotional well-being and cognitive performance are better supported by buildings and urbans spaces that allow connection to the natural environment. Daylight and sunlight in a building are, of course, direct links to the ever-changing light outdoors, so they can also help users of the building to feel more connected to the outdoors.

This practice holds that buildings and urban spaces should be designed to go beyond necessary utilitarian, task-oriented requirements: buildings should promote well-being and give delight. Daylighting, careful use of indoor sunlight, and variation in colour and pattern of light should be utilized in building design:

  • To support occupant well-being by addressing the basic human need for sensory variability.
  • As connection to the natural world outdoors to address the innate human preference for connection to nature.
  • As a palette for designing for the senses, for the intellect and for the human spirit, not just for the eye-as-visual-organ.

If you, too, consider natural light to be a key aspect of sustainable design, and you think buildings and urban spaces should be carefully designed to make best use of daylight and sunlight, then perhaps you should incorporate into your design process the advice and analytical techniques that this practice offers:

  • Average Daylight Factor calculations
  • Detailed simulations of the variability of daylight in spaces, through the day and the year
  • Sunlight penetration and shadow studies
  • Vertical Sky Component calculations
  • Annual Probable Sunlight Hours calculations

You can contact Catherine Alexandra on 020 7148 3450 or 01933 788 500 or by using the contact form.