A roof window can pivot or hinge, and the choice changes how you use the room. A top-hung unit has its hinge at the head of the frame and opens outward, so you can stand beneath it and push it up to a fixed angle. The centre-pivot kind rotates about a bar at mid-height, with the top of the sash swinging in as the bottom swings out. The pivot makes the window easy to clean from inside and gives a wide view when it is open.
Height of the ceiling decides which suits. In a standard bathroom, the handle on a top-hung unit sits at the bottom, within reach. On a centre-pivot, the handle is at the top, so you may prefer a motorised opener or a pole. We note the height at the survey, because a handle you cannot reach is a window you will not open.
The glazing itself is a separate question. Laminated glass is a good choice over a bathroom or bedroom, because it is tougher and cuts rain noise. Toughened outer glass is common, and a coating on the inner pane keeps heat in.
Neither style is better. The right one depends on the room, the person using it and how often the window needs to open.
Then there is the matter of the blind. A bathroom window that faces the sky is not overlooked, but early summer sun can wake a sleeper well before the alarm. Roller blinds, pleated blinds and blackout blinds all run in side tracks fixed to the frame, and an electric version can be wired in at the same visit if you want one. Fitting the right blind at the same time costs less disruption than coming back later, so we raise the question at the survey and note your choice on the written quote.
