It determines the prosperity & Happiness ManaiadiSastram and Vaastuprevail from Gold olden days. The preferable land is either Square or rectangle. Ground Level of South & West should be higher than North and East. Bore Well, Storage tank should be in the North / East Portion underneath the ground level. Light Weight materials here in East/ West heavier than one in the South/ West.
In Construction the building southwest is the controlling factor. So master bedroom is to be located. Family head should live here. The Kitchen should be either South East or North West part of the building. Toilets should not come in South West and North East Corners.
Head Position in the bedroom is preferably, on the south & West directions, but at all on the north direction of the room. Facing of the entrance; all four sides are equally good, provided the entrance is properly placed in 1 to 6 Parts out of 9.