Revisions log for question
How much light does the window let in?

Let's say we have a room of 20 m². Now plan a window with a glazing area of 2 m² for this room.

How bright is it? How bright is the room with 10 m² of glass? How much m² of window is unlikely to make the room brighter?

Is there a rule of thumb with which to figure this out, or perhaps even a calculator or small formula to figure it out?

Maybe even with outside influences such as a nearby tree, carport, neighboring house, balcony over it, north/east/south/west orientation of the window?

• germany
• bavaria
• window light