– are vital to reliably assess both the performance-effectiveness and the cost-effectiveness of daylighting
systems. I believe the wider adoption of climate-based
daylight metrics would greatly assist in the evaluation
of these daylighting systems and the marketing of
those shown to be effective. These theoretical and
technological advances have the potential to radically
improve our perception of what constitutes good
daylighting in buildings, both in terms of basic design
parameters and the use of novel glazing materials thus
paving the way for daylighting guidelines and codes
that lead to the reliable and robust production of truly
healthy, low-energy buildings. But in the meantime,
the realisation of a ‘well-tempered’ daylit building in
which the fixed (static) architectural form provides
both good daylighting and effective solar protection,
remains more of an art than a science.
l John Mardaljevich is professor of building
daylight modelling at Loughborough University.
He has pioneered the development and application
of climate-based daylight modelling
Above: Seattle Central Library
designed by OMA and LMN.
The geometry provides shade
or unusual quantities of
daylight where desirable.
Opposite: detail of low-iron
stainless steel screen based
on Islamic geometry used for
Banque Marocaine du Commerce
Exterieur (BMCE) branches by
Foster and Partners