The ancients designated a crucial part of the home as a sacred sanctuary, a fortress of purity to which dwellers could retreat before dawn each day, to commune with their higher nature and with God and the Gods. This center of spiritual force is called devatarchanam, the "place for honoring Divinity." Sacred architecture places it in the northeast corner, the realm of Isana, where its potency naturally flourishes.

Love and joy come to Hindu families who worship God in their home through puja, meaning adoration or worship. Through such rites and the divine energies invoked, each family makes the house a sanctuary, a refuge from the concerns and worries of the world. The center of that sanctuary, the site of puja, is the shrine, mystically tied to the temple to which they pilgrimage weekly.

The home shrine is also the locus for private and group meditation, prayer, mantra recitation and devotional singing. Special pujas are performed here for birthdays, festivals and other special family occasions.

Its sanctity is protected by never using it for other purposes. This space is meticulously cared for, kept immaculate and elaborately decorated to look like a small temple. It should be well-lit and free from drafts and household disturbances. The altar is generally close to the floor, since most of the puja is performed while seated. But when there are small children in the home it is often higher, as to be out of their reach.

Source : Extracts from : http://www.hinduism-today.com/1997/8/
More on Puja : http://www.hindunet.org/puja/
2000-Oct-16 5:36am webmaster@hindunet.org