DAYLIGHT IN DESIGN
SEEING THE LIGHT
Multiple studies have shown exposure
The eff ects of daylight are well-known in the architecture community,
to natural light aids health and
but are they really understood? Here, Velux Modular Skylights asks if
well-being, increases productivity,
improves mood and even helps
we still in the dark when it comes to daylight design. to retain staff, highlighting a need for a greater
focus on daylight design and more comprehensive
government lighting standards.
Natural light is an essential design element and
according to Andrew Bissell, lighting director at
Cundall, daylight design should be involved from
the very outset of any project. Every detail from
where a building site is located, its orientation
and the daylight exposure it receives, to window
placement, the balance of thermal heating and the
use of glazing can infl uence building comfort.
“Daylight design needs to be involved at the
planning stage,” says Andrew, “any later and its
effect is already limited.
“It’s about how light enters a space – thinking
about all the rooms, not just basing it on digital
models and numbers but also lighting patterns and
ensuring light is distributed evenly in every space.”
According to Laura Phillips, lighting designer and
associate director at Arup, many architects tend to,
understandably, base their knowledge of daylight on
past projects. “There is a tendency to shy away from
specifying daylight systems, as they can be costly to
a project if not considered and integrated early on,
and the benefi ts can be diffi cult to sell to a client,”
“Greater collaboration on daylight quality is
needed – early on within the brief – to create
buildings that allow daylight to be utilised to its
Daylight is a commodity
Daylight, when harnessed correctly, has been shown
to have massive energy benefi ts, offsetting the need
BUILDING PRODUCTS | SEPTEMBER 8
for less healthy artifi cial lighting while cutting energy
costs by 30-45%.
Research has also shown exposure to daylight
throughout the working day can improve mental
function – including memory and speed of work –
between 10 and 25% and improve productivity by
up to 15%.
Greater access to daylight, and something as
simple as having a desk with a view, can also help
with staff retention as employees are shown to be
happier and take less sick days.
The artifi cial versus natural light debate
A lot of new lighting technology has been designed
to replicate natural light, but it offers no real benefi t.
As much as LED and other artifi cial lighting claims
to mimic natural light, it has a very limited spectrum
and lacks the naturally occurring colours vital for
proper visual performance and the regulation of
hormones and neurotransmitters in the brain – such
as cortisol, which is related to stress, and melatonin,
a prerequisite to sleep.
That being said, adequate levels of daylight
throughout the day are not always possible due
to the ever-changing position of the sun, window
orientation and other factors.
Layouts need to be designed to balance artifi cial
and natural light, taking into consideration façade
refl ection, the sun’s movement, glare, shading, light
intensity and automation – to ensure spaces are
evenly lit, there is good patternation and external
and internal elements work together.
Most importantly, lighting needs to suit the
function and needs of the occupants of the space.
Offi ces, laboratories, leisure centres and especially
schools all have different, specifi c requirements.
A new standard for daylight
There is growing demand for more detailed
daylight standards and clearer parameters to
be introduced to ensure daylight design is
implemented at the planning stage. While recent
years have seen a positive step-change with the
move from daylight factors to climate-based
daylight modelling, there is now a need for further
changes, such as introducing the spectrum of the
light to the matrix, as well as more measurement
positions relating to the eye position and viewing
direction of occupants.
Andrew Bissell believes: “We need to move
away from current light measuring tools as they
just look at the amount of light and not how it
affects occupants. Measures like melanopic lux and
circadian stimulus – which seeks to measure both
the visual and biological infl uences of light – and
greater clarity on what ‘health lighting’ means need
to be made regulatory standards.”
Daylight design is still considered a ‘nondiscipline’
but the more we learn about daylight,
the more we see the need for professional bodies
to infl uence government and improve standards.
The next Velux: Design a Brighter Future free
breakfast events are taking place in Birmingham
(23 Oct) and Glasgow (7 Nov). To register, visit
Eventbrite.co.uk and search for “VELUX”.