Use the 'Show Area Text' feature of the fill tool to make wall and glazing area measurements a breeze.
Set up the fill tool with a fill you like (I use 25%) and the layer 'xRef Measurement.HIDE.' (Always hidden. Show it.) Turn the outline on.
On each elevation, draw a fill encompassing the wall area. Place the area text somewhere in the middle.
Drag *a copy* of this fill up far enough to get it clear of the elevation. This doesn't need to be precise.
Select the fill still on the elevation. With the box, or rotated box, geometry method, draw rectangles on the door and window openings. Watch with fascination as each box lowers the area value. Neat. O.
As you finish with each elevation, note the wall area (above) and the wall minus glazing area (below). Subtract the lower from the upper and you have your glazing area. Add the values from each elevation. Divide the glazing total by the wall total, and you're done.