Separate comfort, operation and water-management issues before deciding on a window project.
Safety first
Never obstruct an emergency escape opening. Do not lean from an upper-story window or remove heavy glass. Condensation between panes and indoor surface condensation have different causes.
Checklist
List windows that stick, will not latch or have damaged glass.
Check accessible weatherstripping and seals for visible wear.
Record whether condensation is inside, outside or between panes.
Look for staining below frames after rain.
Keep exterior drainage openings clear according to the manufacturer's instructions.
Record comfort concerns by room, exposure and season.
Compare whole-window U-factor and solar heat gain coefficient on NFRC labels.
For replacement, verify emergency escape requirements and flashing details.
Save labels, installation records and warranty terms for future repairs.
