Research Output

Daylight illuminance modelling for the United Kingdom and Europe.

  This thesis highlights the benefits to occupants and owners of buildings who utilise
daylight effectively. Many cases of absence are related to depression or Seasonal
Adjustment Disorder(SAD) which results from inadequate exposure to daylight in the
work place. The use of artificial lights has been linked to minor as well as more serious
ailments such as cancer and increases in cases of miscarriage.
The use of daylight in buildings from economic and environmental perspectives is the
main concern of the thesis. The work and analysis of this thesis have produced two new
illuminance models. In addition detailed illuminance and irradiance data for Central
Scotland were recorded which has previously not been available.
A comprehensive study of luminous efficacy research was undertaken in Chapter 3 which
evaluated a complete range of models. Furthermore the luminous efficacy of various UK
and international sites were compared to examine climatic differences. The development
of a new slope illuminance model which more accurately predicts external illuminance for
all sky conditions was shown to perform consistently better than previous models. This
was due to the new model's treatment of the sky background diffuse component utilising
an anisotropic form as opposed to the traditional assumption of an isotropic sky
background diffuse component.
The availability of sky luminance distribution data from introduction of sky scanners
enabled innovative daylight illuminance factors to be developed. These factors model the
distribution of the sky's hemisphere under all levels of cloud cover and calculate the
internal illuminance taking into account window size, glazing type, orientation and time
of the day. The development of the daylight illuminance factors has been shown to
significantly improve the energy efficient design of buildings in comparison to the current
practice of employing the sky factor method.
The daylight illuminance factors were used in a modelled building design scenario to
assess their performance and to examine energy efficient design. Lighting controls and
various glazing types were analysed to study their impact on a buildings energy
consumption. This study also incorporated an embodied energy analysis which
considered the energy consumption of windows in manufacture and operation.

  • Type:


  • Date:

    31 October 1995

  • Publication Status:


  • Library of Congress:

    NA Architecture

  • Dewey Decimal Classification:

    720 Architecture


Angus, R. C. Daylight illuminance modelling for the United Kingdom and Europe. (Thesis). Edinburgh Napier University. Retrieved from


daylight; Seasonal Adjustment Disorder; environmental concerns; illuminance models; irradiance; luminous efficacy; anisotropic; sky luminance;

Available Documents