Windows of Opportunity have to be seen from different angles:
Old Windows from a different perspective. One way is to see other windows opening to the other side of environment- or seen only as confrontations of one side only. The enticement is to let history come to you or looking past one perspective into another and another. Flatness or depth, use the window for all it is worth and keep your perspective growing and love what you find. An artist finds more than what is there just by mulling everything over and giving time a chance to speak out at you. You might see something entirely different.
I have built windows and know what carpentry needs to fit the structure in and keep it there.
And a real big deal is watching time affect wood, especially unpainted wood, with regards to color and quality of decay on surfaces that reflect time and craftsmanship.
Once you see aged buildings still standing you have immediately set up an investigation into your age compared to it's age. The knowledge of what a building was meant to be and how it performed is thrown in with your age and all you have done to build similar facilities.