A Simplified Method for Optimizing Daylighting Hours in Summer Climate Condition

  • Ahsanullah SOOMRO
  • Saleem Raza SAMO
  • Mahdi Hassan MALLAH
  • Imran Ahmed SAMO
Keywords: Windows opening, daylighting utilization, indoor temperature, mathematical model, thermal comfort


The prediction of indoor temperature is indispensable for optimal use of daylighting and maintaining thermal comfort inside any building,
which can be made using mathematical models. The models require long term input data of climatic parameters, like solar radiation, ambient
temperature, relative humidity, and wind speed. Since, it is difficult to get such data of required parameters in developing countries. Therefore, a
model with less number of input parameters is needed to predict the level of indoor temperature. In this study a simplified method was proposed
for determination of optimum daylighting hours in summer season at Nawabshah, Pakistan without any structural modification using only
input of outdoor temperature. Outdoor temperature was measured for an entire year and indoor temperature for one month. The relationship
between these parameters were made using curve fitting tool MATLAB software. The model equation was formulated for prediction of indoor
temperature and optimal use of daylighting hours. The model results revealed that the daylighting can be used for 1008 hours in any summer
season of the year. The model was validated for a one month input data with ASHRAE standards using CBE thermal comfort simulation tool.
The proposed model and simulation results were found to be identical.