Windows are also openings but unlike doors are open most of the time. Windows are considered a break in the wall. Hence they facilitate an exchange of energy with the surroundings for larger periods.
Windows are often equated to the eyes of the house. It is through the window that one has to view the world.
There should be windows on all external walls of a building for best results. But that is only for the home. Never have windows on all walls for any room.
A window should open out side. An outward opening window welcomes more energy inside the house. Windows opening within the floor space are considered very bad. Rooms with such windows are deficit in energy.
Sliding windows are not as powerful as swing windows since they cannot open for the full width. Hence they allow only a partial flow of energy within.
Windows should not be locked from outside or inside. Trim all tree branches that may be hiding a window. Very large windows are bad. They have to at least be broken up into smaller units.
Windows should be at reasonable heights. Those that are too high can make a personal feel stifled and that are too low can make a personal feel vulnerable. One can even use curtains or blinds to close the window space in the night.
