This study uses the thermal time constant to determine the thermal load of different building materials. A nomograph is developed to read the heating and the cooling load at any latitude. The vertical axes and the zeros points are defined according to the thermal time constant of materials.
The study introduces a very easy manner for obtaining the thermal load of walls . It is applied for both Lat 30o 8/ and Lat 51o 7/ and is in a good agreement with the calculated results.