How to clean in between old double hung wooden sash windows

[debodun]

I have really old window casements and I'm at loss of how to figure out how to clean between the outside and inside window. They probably haven't been done in decades and they are getting so dirty, I can hardly see out. I cleaned he inside panes and the paper towel was black with gritty dirt. Makes me wonder how they get so dirty on the inside, so you can imagine what they are like in between the sashes and on the outside. Here is a photo of one take from outside at a time when I tried to install an air conditioner.

 

[RadishRose]

Call a professional. Think of all the decades you've never cleaned your windows; you've certainly saved up enough money for a through cleaning.