Windows are among the most challenging aspects of a historic tax credit (HTC) project. Replacement is not automatic–an owner must make a strong case for replacement by documenting that the existing windows are beyond repair. Identifying an appropriate replacement window and presenting that window for approval can be a time-consuming process that can lead to project delays. After a replacement window is approved, the lead time for manufacturer can add months to a project schedule. Attacking the issue early is crucial to keep projects on schedule and on budget.