Basement – How to correctly measure this basement window for a replacement


I have three of these metal-framed basement windows which I would like to replace but I am unsure of what dimension I should measure and use for the replacements.

Full Window

Initially I measured the outside dimension (32 1/2" x 16 1/4") but on closer inspection, it looks like the metal is just folded up against the concrete. This leads me to think I should use the inside dimension (30 1/2" x 14").


What is the correct way to measure for replacement windows in this case?

EDIT: Included some outside pictures

Outside 1

Outside 2

Outside 3

Best Answer

If the metal frames are rotted to the point of being unusable you can remove them. It will not be easy. They may have anchors embedded into the foundation. Until you remove the frame you can't tell what the size of the opening will be. You may also need some masonary skills to repair or prepare the opening to accept the new windows. Then you have to decide how the windows will mount to the concrete. You can frame the opening with P/T wood and then anchor the new windows to the wood or metal frames anchored to the original masonary opening. The opening may require a bit of work to set new metal windows. Another option is glass block set diectly into the opening if ventilation isn't required.