Is granite or marble good for windows?

No. The chaukhat is the four-piece frame, and a window or glass above it is not counted in the door aay, because fixed glass stays closed; glass that opens and closes would be counted. Fixed glass above a door is itself used as a remedy.

In interior vastu a wrong door is treated only with symbols and similar items, since the full door treatment alone would take about five classes. For South door defects the class gives bandhanwars of stone or gems, a toran of copper and wood, and a red triangular swastik bandhanwar hung on a Saturday or Tuesday. In the South only S4 is a good pada, and it suits those with Kark, Makar or Kanya rashi, mulank 9, or an exalted or own-sign Mars.

It depends on the nature the occupants need. Those who must keep firmness, such as kings and military people, use stone, while wood always represents softness, so those who want a gentle nature use wood. The door and its frame shape the nature of the people: if you need to become tough, make the dehleez of hard stone.

A door is placed by pada, but a window does not work on the surface current: currents are dense near the ground and lighter higher up, so positive energy stays higher, which makes ventilation a must. Windows and ventilators bring in clean air and push the negativity of the house out, so they should open outward, while the main door opens inward; sliding windows are acceptable. Keep windows in even numbers, two-shuttered if possible, in one row at one level, with a window beside the main door; open all windows in the morning and keep the left (Chandra swar) window open during the day.

Curtains represent the air element: they move only when air comes in. The main door, every door and every window also represent the air element.

Yes. The North results then start coming, though not fully; you get as much as is open. Through a window only air comes in, whereas people come in through the door.