The church was designed by the architectural firm Anker & Hølaas and created by Selvaagbygg.

The altar decoration was created by Zdenka Rusova in 1976, a brass cross on a painted surface with flame pattern.

On the side walls are twelve images with motifs from life of Jesus, created by Ewa Calber Westelius in 1996.

[2] The church organ with 19 voices from 1991, from Ryde & Berg is said to be among Oslo's best.

[1][2][3] Fossum Church is listed by the Norwegian Directorate for Cultural Heritage.