A skylight window for being installed in a roof of a building, the skylight window comprising: a window frame having four frame side members, a window sash having four sash side members supporting an insulating glazing unit having multiple layers of glazing, the window sash being movable in relation to the window frame between an open and a closed position of the skylight window, a first of the frame side members being associated with a first of the sash side members, the first frame and sash side members extending in a respective longitudinal direction, the IGU having an exposed interior major surface for facing an interior of the building in the closed position of the skylight window, the exposed interior major surface being of an interior pane of the IGU, the interior pane comprising a side surface extending substantially along the first frame member and first sash side member, a height direction extending perpendicularly to the interior major surface in the closed position of the skylight window, the IGU further having an exposed exterior major surface facing in an opposite direction towards an exterior in the closed position of the skylight window, the first frame side member comprising a lining panel protrusion located lower than the exposed interior major surface of the IGU in the height direction, wherein the lining panel protrusion protrudes away from the IGU, the lining panel protrusion comprising a first surface for abutting a surface of a reveal panel or lining panel so as to position the reveal panel or lining panel, wherein the first sash side member comprises an IGU supporting leg for supporting the IGU, the IGU supporting leg being defined by the part of the first sash side member that is located below the exposed interior major surface and within a periphery of the interior pane of the IGU and supporting the exposed interior major surface of the IGU, and wherein, in the closed position of the skylight window, the first surface of the lining panel protrusion extends within the periphery of the interior pane and the first surface of the lining panel protrusion is positioned farther away from the side surface of the interior pane than the IGU supporting leg in a lateral direction extending along the exposed interior major surface of the IGU, and c h a r act e r i zed in that the exposed interior major surface of the IGU is located in the height direction below a top of the first frame side member. a window frame having four frame side members, a window sash having four sash side members supporting an insulating glazing unit having multiple layers of glazing, the window sash being movable in relation to the window frame between an open and a closed position of the skylight window, a first of the frame side members being associated with a first of the sash side members, the first frame and sash side members extending in a respective longitudinal direction, the IGU having an exposed interior major surface for facing an interior of the building in the closed position of the skylight window, the exposed interior major surface being of an interior pane of the IGU, the interior pane comprising a side surface extending substantially along the first frame member and first sash side member, a height direction extending perpendicularly to the interior major surface in the closed position of the skylight window, the IGU further having an exposed exterior major surface facing in an opposite direction towards an exterior in the closed position of the skylight window, the first frame side member comprising a lining panel protrusion located lower than the exposed interior major surface of the IGU in the height direction, wherein the lining panel protrusion protrudes away from the IGU, the lining panel protrusion comprising a first surface for abutting a surface of a reveal panel or lining panel so as to position the reveal panel or lining panel, wherein the first sash side member comprises an IGU supporting leg for supporting the IGU, the IGU supporting leg being defined by the part of the first sash side member that is located below the exposed interior major surface and within a periphery of the interior pane of the IGU and supporting the exposed interior major surface of the IGU, and wherein, in the closed position of the skylight window, the first surface of the lining panel protrusion extends within the periphery of the interior pane and the first surface of the lining panel protrusion is positioned farther away from the side surface of the interior pane than the IGU supporting leg in a lateral direction extending along the exposed interior major surface of the IGU, and c h a r act e r i zed in that the exposed interior major surface of the IGU is located in the height direction below a top of the first frame side member.