This article could use and 11th item entitled “Use Epoxies to Repair Rotted Wood“, but even as-is, it is a great checklist for improving the performance of wood windows.

10 Ways To Make Old Windows Work Like New

Window Repair and Weatherization Guidebook- published by the Architectural Heritage Center:

Window Repair Guidebook

Saving Windows, Saving Money- Evaluating the Energy Performance of Window Replacement and Retrofit-  A report produced by the Preservation Green Lab, a project of the National Trust for Historic Preservation:

Saving Windows, Saving Money