Vastu Shastra holds great importance since time immemorial. Its significance has been mentioned clearly in our Puranas and Upanishads. However, according to Hindu scriptures, there are three types of Graha Pravesh which hold utmost importance. They are as follows:
1. Apoorva- When a newly selected land is used to construct a new house and the first entry into such a house before beginning to live in it is called the Apoorva (new) Graha Pravesh
2. Sapoorva- When a person comes back after a long travel abroad or after migration from elsewhere, the first entry into such an existing house to live in it is called Sapoorva Graha Pravesh.
3. Dwandwah- when a house has undergone renovation or reconstruction after getting damaged due to unforeseen mishaps like fire, water flood, electricity, wind etc. and the first entry puja into such a house is called Dwandwah (old) graham pravesh.
The purity of Panchang and the arrival of an auspicious muhurat (time) is very vital for Griha Pravesh according to Vastu scriptures. However, it is the perfect auspicious time or muhurat should be strictly followed for Apoorva Graha pravesh while for reconstructed house or migration the purity of panchang needs to be strictly adhered to.
Vastu Shastra says that living into any house should be started only after making needful offerings and sacrifices to the Gods and only after having followed all Vastu norms pertaining to it as mentioned in our scriptures. However, if a house has been built with grass and leaves, it can be entered for living on any auspicious day. But when bricks, stones, mud, cement etc are used for the construction of a house, a special auspicious Muhurat needs to be taken out when the Sun is in the Uttarayan. Also, Griha pravesh ceremony should be comducted and completed during the daytime.
The most auspicious months for Griha pravesh are as follows:
Magh leads to gain of wealth
Falgun brings about gain of children and wealth
Baisakh helps in growth of wealth and prosperity
Jeshtha blesses the owner with the gain of son and cattle.
Other than these, Kartik and Margshishir months reap medium benefits for Griha Pravesh puja. However, Griha Pravesh puja conducted in the month of Ashadh, Shravan, Bhadrapada, Ashwin and Paush are considered to bring about losses , troubles and fear for the owners and hence should be avoided.
Also, Tuesdays should never be chosen for a Griha Pravesh puja. Similarly, dates like 4th, 9th, 14th and 30th (amavasya or no moon day) as per Hindi calendar should be avoided for the same.