The National Trust for Historic Preservation has created the following window preservation toolkits and information on understanding window design and construction, repairing, and guidance when repairing/replacing.

• Toolkit No. 1 -  Repair or Replace Old Windows (6 MB, PDF)
• Toolkit No. 2 - Window Types, A Residential Field Guide (5 MB, PDF)
• Toolkit No. 3 - 10 Reasons to Repair Your Old Windows (350 KB, PDF) 

The National Trust for Historic Preservation has also created the Save the Windows website and their Partner With Us effort for preservation organizations and private citizens.

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