People using the NSC next week will need to use the rear of the building next week.
Maintenance work will be carried out on the atrium roof on Monday.
It means from 6am to 6pm access will only be via the rear of the building.
Users will still be able to make use of the gym, spa, squash courts and bowls hall.
Classes will be held in the secondary sports hall.
The café, reception and main sports hall will not be open during these hours.
After 6pm access will return to normal.