VELUX roof terrace consists of a combination of two sections GEL+VEA/VEB/VEC. The upper section (GEL) is placed in the sloping roof. The lower section (VEB) is installed vertically below upper section.
Lower section VEB is a side-hung vertical window element, which is operated with a handle on the side sash. It opens to the left (seen from the inside).
The sash can be opened/closed by operating a handle on the side sash when upper section GEL is open.
Lower sections VEA and VEB cannot be opened without first opening upper section GEL. Lower sections VEA and VEB open outwards.