The elliptic church hall is bathed in daylight, which passes into the hall from the narrow skylights between the rock wall and the copper ceiling dome. The inner surface of the dome is clad in copper tape requiring a length of 22 km. The diameter of the dome is 24 metres, and the highest point is 13 metres from the floor.

There are 180 skylights in the ceiling, they let through light also during the darker winter months and also when covered by snow. The light fixtures have been modernized and changed into LED lights.