Window design has evolved continuously over the centuries, so windows can be of invaluable assistance in dating buildings, and later phases of alteration. The importance of windows does not just rest in their overall appearance, but in details such as their construction and materials, their fittings and mechanics, and even the very glass that is the reason for their existence.
Here is a historic window guide by www.windowanddoorguys.com that looks at the evolution of old-house windows.
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