Together with Viksjø's H-Block from 1958, the Y-Block, represents a key work of Norwegian post-war modernism. Also, the facade's mural by Pablo Picasso contributes to the significance of the building.

Demolished in 2020. The wall sections with the Picasso artworks were removed before the demolition and later installed in the new A-blokken government building (last updated on January 29, 2025).