On Apr 15, 2:11 pm, "Arkadiy" wrote:
Hello everybody,

I must be missing something... I want to replace a window, but I
can't measure "unit size" or "rough openning" while the old window is
still in. How do I figure out the correct size to buy a new one?

Thanks in advance,

Arkadiy

Carefully pry off the old interior trim. This may allow you to
measure the rough opening. The rough opening ma be covered with
drywall but you can carefully trim it back to reveal the edge of the
opening.

Alternatively, you could measure the size of the old window frame
itself and add perhaps 1/2 inch to both width and length. Another low
risk alternative is to go ahead and remove the old window completely
to measure the RO. Cover with plywood until the window comes in.