Vastushastra essentially deals with two energy sources – the solar energy flux and the geomagnetic energy flux. The science of vastu aims at controlling the flow of these energies in a vastu by selecting proper directions and alignments for the vastu. Location of doors, windows, color scheme, flooring patterns, planting of trees – all these parameters play an important role in enhancing energy field for human being to live in harmony with nature.The south, southwest and the west are the directions subjected to excessive cosmic particle activity.

Conventionally, the north is source and the south is the sink for electromagnetic flux lines. Sub atomic particles travelling along the geomagnetic flux lines end up at the southern tip. Excessive cosmic radiation particles, particularly, positively charged particles, enter the earth from the west rather than the east. Specially, in Indian context, excessive solar radiation come from south, southwest, and southeast directions. It is always suggested that the compound walls in the south direction should be greater in height and thikness. Also, the plinth of all the rooms in the south should be more. It is suggested to construct basements, underground water tanks and extra floor on the south side, with terraces towards the north and east directions.