Where is the moisture?
Record whether it appears on the glass, at a frame corner, or on the surrounding ceiling, and whether it follows rain. VELUX service examples distinguish profile condensation, corner-key repair, and glass replacement for particular models.
When does the unit need replacement?
Replacement fit depends on model, opening size, roof pitch, and compatible flashing. VELUX replacement guidance and DOE building-science material explain why the unit and roof connection need separate review.
What happens to the light shaft?
If roof work opens the shaft, protect the room and include trim or ceiling restoration in the project plan. High ceilings or stairs also affect safe interior access.

