Frame the window openings as you’re framing the walls. To find the size of the openings, measure the windows and add 1-1/2-inches to the width and height. This leaves space on all sides of the windows ...

Mechanical flashing is then cut to serve as an exterior apron to the sill, running about 5 inches up the two sides of the window opening and extending 9 inches to both the right and left of the ...