SUN SHADOW ANGLES FOR ARCHITECTCS With special reference to The UAE

Abstract

Often the greatest source of heat gain is the solar radiation entering through
windows. Heat is then trapped in; because of the "greenhouse effect" shading the
windows is one of the most effective method within the reach of the architect for
reducing this heat gain. This is nowhere more necessary than in a country like the U.A.E.
but we find the architects here often ignoring this important environmental aspect of
design. This is partly due to the lack of relevant local meteorological data plus the
complexity of the procedure involved ;and partly due to the misconception that such
aspect looses much of its significance when the building is air conditioned .
The aim of this paper is to simplify the issue and promote greater attention to this
aspect by architect designing for the U.A.E.
Based on the solar azimuth and altitude angles for the U.A.E. for the
representative latitude related to local civil time, a number of useful tables to the architect have been prepared . One gives the hourly shadow angles and direction for each month. Then a set of tables to define the shadow angles for buildings of various possible orientations. In addition effective temperature isopleth for the U.A.E. has been constructed, with the shading line definded on both the isopleths and the solar charts. This is done in order to give greater insight into the overheated period of the U.A.E., and facilitate future possible use of shadow protractor, when necessary.