Your original windows add a lot of character and charm to your home. They have weathered more than 50 years of use and can have a much longer life span with some maintenance. Chances are they have survived as they are made from some very solid, high quality wood assembled with fine craftsmanship. INSIDE the existing window openings making your visible light less. Antique windows are made of old growth wood which is more dense and rot resistant. Joints may loosen up or rot may be present, but all can, and was designed to be repaired indefinitely.