That doesn't matter for portable AC. Most people build a plexiglass or foamboard plug for the open window. Some products are sold already set up like this. If y

That doesn't matter for portable AC. Most people build a plexiglass or foamboard plug for the open window. Some products are sold already set up like this. If you can fit a casement AC that also probably doesn't matter. You can probably remove the window too I'm guessing.