Vastu Shastra has great importance for entrance door in a home, as this is the place from where energies, either positive or negative, enter and exit a house. Having said this, it is obvious that if more negative energies are entering a home from main door then people in the house will not prosper. On the other hand, if more positive energy is entering a home then the residents will prosper.
The main door of the house should be the largest in size as compared to the other doors. Vastu Shastra says that it is the front door through which positive energies enter the house and hence it should be big in size. For luck and prosperity, the main door must be more beautiful as compared to the other doors.
Since the main objective of Vasthu Sastra is to maximize the energy inside the house, it is recommended not to have arched doors and windows as they distort the energy flow.
The back door should be positioned directly opposite the main door.
The house should have an even number of doors and Vasthu recommends there are more doors in the north and east than south and west.