National Trust for Historic Preservation offers "Weatherization Guide"

The National Trust for Historic Preservation has implemented its "Weatherization Guide" for Older and Historic Buildings."

The guide serves as a comprehensive resource for homeowners who want to make their homes more energy efficient without spending a lot of money. One of the main goals for this guide is to provide insight on making energy efficiency improvements without compromising the historic character of one’s home.

The Weatherization Guide includes a section with advice for retrofitting old windows and answers many questions on whether it’s best to repair or replace windows.