Roof day-lighting elements and architectural roof glass are striking and desirable building features that historically come at a high cost – leaks, energy loss, thermal discomfort, and condensation issues. Next-generation roof glazing is addressing these issues and developing roof glass elements designed to be thermal-bridge-free, and suitable for high performance and Passive House envelope needs. Fenestration of all kinds requires special attention, but failures in roof glazing can unravel the thoughtful planning put into the rest of the building. The potential for thermal bridging, overheating, cold air convective currents, and air or water leaks can dampen or destroy the gains of free daylight and visual comfort.