The best place for the pooja room is the North East of a house also called the Ishaan zone. Lord Shiva is the presiding deity and Jupiter is the planet for this zone.
In a house with a ground and an upper floor, the pooja room should be in the ground floor. Pyramid shaped rooms are good for pooja rooms.
Pooja room should not be above, below or next to a toilet or under a staircase, or in a storeroom or basement.
In case a separate room is not available, Vastu permits pooja in the kitchen with placement of God and the lamp in the North East.
Pooja in the bedroom of a married couple is not permitted. If this is unavoidable, then the pooja area should be covered with a curtain or little wooden doors on all sides.
Idols of deities should not be placed in an alcove in a wall. Idols should be 1 inch away from the walls. Ideally idols should be not taller than the height of your thumb. Taller idols need the sanctity maintained in temples which is very difficult to achieve in a home.
Broken idols or those brought from an old temple should not be used in the pooja room.
Doors and windows of the pooja room should be in the North and East. The doors should ideally have 2 shutters, and door closers should not be used.
The colours of the pooja room should be white marble on the floor and white, light yellow or light blue on the Wood or marble is the best material to be used for the pooja room.
Never conceal any money or other valuables in the pooja room.
Do not place photos of deceased persons in the pooja room.