retractable roof opening time

The retractable roof opening time for any structure is the minimum amount of time it takes to open a mechanically retractable roof completely, from its fullest closed position to its fullest open position. This applies especially to convertible stadiums.

This is a measurement of the installation as it runs, not a property of the building. Lift speeds are reset, drives are slowed as they age, and a roof that opened in ten minutes when new can take longer later, so a duration belongs to the date it was taken on.

Where several installations exist, the value describes the one named in the field and not an average of them.