The electrolysis hall of Sør Norge Aluminium in Norway was equipped with a roofhouse with mechanical ventilation.
The mechanical ventilation was outdated, and the decision was made to remove the roofhouse and replace the mechanical ventilation system with a gravity ventilation system.
Colt Labyrinth
Colt took advantage of the construction opening thus produced to fit a gravity ventilation system, type Labyrinth, on a steel upstand.
The system is 1700 metres long and 4 metres wide.
The great advantage of this system was that the width could be adjusted to the roof opening.
New construction
During implementation of the project, Colt was commissioned to equip the 430 metres extension with this system as well.
