How can I manage a drop ceiling potentially overlapping the top of a window?

Question

Modifying a garage to turn it into bedrooms, I will be hanging a drop ceiling to cover up pipes, wires, etc., overhead. An existing pair of windows (pictured) goes almost all the way to the current ceiling, with only about 2" of trim above the rough opening. Due to a water pipe about 7" below the ceiling, my drop ceiling would overlap the window's opening by about that much. (I haven't done a drop ceiling before and I'm not sure what the thickness of that hardware is.)

Certainly one option is to replace the windows, buy shorter windows, and wall in the top part of the rough opening to make a smaller opening that will fit below the drop ceiling.

My question, though, is: can I continue to use the existing pair of windows, even if they are partially overlapped by the drop ceiling?

• If so, are there problems I should expect and special measures I should take?
• If not, why not?

Clarification: the window on the left, and the dog door, are going to go no matter what. I'm envisioning buying another window for the left side to match the one at right, if this is reasonable.

Answer 1

I had an almost an identical situation as you have shown except I worked very hard to eliminate the amount the drop down ceiling came down and was able to get it to work at 3.5 inches. I the built a wood box as shown in my diagram below that allowed the drop ceiling to fit around the box but still allow the window to exist full size.

This picture is a side view looking into the edge view of the window unit. The box is typically made of four pieces of pine boards including the top, two ends and the front face that parallels the window. The amount of projection out from the window will depend upon far back the window surface is from the wall surface and how far down the drop ceiling comes.