The main entrance with South direction is considered as inauspicious for the entrance of the house. Because an entrance should always be placed in the Kuber , Satwik & Indra i.e. North, North East and East respectively.
Placing the Entrance with South direction will first hit the health and then on the wealth of the person residing, hence peace will be lost. The Sun Rays which you get from this direction carries most harsh heat and UV rays in it which are not good for Humans prone for long time.
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