The main reasons behind these Vastu are deep scientific facts, early in the morning, the sun remains in the eastern region which brings in light and quality air into the residence making the space ideal for mediation, prayer, exercise, study, etc.
It is always advisable to place the Pooja room on the ground floor and not on the basement or higher floors of the house. And the placement of idols should face east or northern direction.
The interior design of the Pooja room should make sure that it creates a soothing mood for the worshipper. The paint scheme of cool colours like blue, white, or a very pale yellow can be considered while designing a Pooja room. The Pooja room should always be well ventilated and should be a source of getting in fresh air and sunlight, windows should be planned accordingly.
In the case of small spaces and apartments with no provision for Pooja room, Pooja room can be located on the northeast corner of the kitchen or the living with closed shutter doors.
First choice: North-East Direction or the Centre of the house.
Second choice: East, West Directions of the house or NE quadrant of the plot.
If none of these corners are available, the Pooja can be located in the North-East corner of any room except bedrooms, toilets, and storerooms.