Daylighting is an up-to-date design discipline that promotes greater use of daylight
in buildings. The basic objective is to position transparent surfaces (such as windows,
skylights or continuous glazing) and interior reflective surfaces appropriately so that
natural light can provide effective illumination throughout the day. While an essential
part of daylighting undoubtedly relates to the planning of the building site and the
architectural design of the building envelope, it should not be underestimated that
coordination with two key functions of building automation systems such as artificial
lighting and shading is also essential for its effectiveness.
Daylighting
OPTIMUM USE OF DAYLIGHT
Natural light as a resource
Daylight is the combination of direct and indirect light from the sun throughout the day; of
all the solar energy received at the earth’s surface, 40% is visible radiation. The interiors
of buildings need light to carry out various activities and the natural component is a very
important resource that can have beneficial effects on people and the energy balance.
Recognising this, the EN 17037 standard was published in 2019 to promote the wider
use of natural light - defined as that ‘visible part of global solar radiation’ - for indoor
lighting. The standard provides information on how to use this light component to provide
illumination and limit glare, while also defining principles for calculation and verification
and taking into account the typical variability of natural light throughout the day and year.
The standard applies to rooms which are regularly occupied by people for long periods,
except in particular cases where natural light is incompatible with the nature and task of
the work being performed.
UNI EN 17037 standard defines the fundamental contributions of daylighting as:
• The external view. Openings not only provide natural light, but also allow
occupants visual contact with the area surrounding the building. This is seen as a
positive factor in reducing the fatigue associated with long periods in the confined
environment, providing an opportunity to relax and relieve excessive concentration;
• Protection from glare. When there is direct sunlight, viewing outdoors can cause
glare, a negative phenomenon caused by areas that have a much higher luminance
than the eyes have adapted to in the indoor environment. To reduce this risk,
shading devices should be provided;
• Exposure to sunlight. This factor is of great importance in the quality of the indoor
environment and contributes to the well-being of the occupants, especially in
buildings such as hospitals, homes or school buildings. The use of shading devices
can reduce possible thermal and visual discomfort.
Sunlight
(from the sun)
Skylight
(from clouds
and atmosphere)
��������
light
(from the ground,
vegetation, other
buildings, etc.)
Why is daylight important?
• 63% of people consider daylight to be the most important aspect of a home (Homewise
survey, “Without space + light”)
• Daylight improves visual and psychological comfort and has a positive eff ect on people’s
performance, attention, satisfaction and ability to learn
• Daylight relieves seasonal aff ective disorder (SAD, a form of depression)
• Exposure to sunlight has been shown to be an eff ective treatment for sleep disorders
• Daylight through windows is the key factor in providing the high levels of light needed to
support the functioning of the circadian system.
(source: www.lrc.rpi.edu)
SMART LIGHTING
SMART LIGHTING
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