TKM Gråmølna consists of an older building, Gråmølna, which was built as a steam mill by Anders Graae in 1840, and a modern extension, which was designed by PK Arkitekter and inaugurated in 2008. When Graae's mill/Graaemølna was new, it was wedged between Innherredsveien and the beach, but after dredging and expansion of the harbor area, it is now well inland. It functioned as a mill for only a few years, and in 1866 a boys' school was established in the building. From approx. in 1900, the building was used for other public activities, such as a police station, a health centre, a food station for the needy, a welfare room for the elderly and a work room for children. When the Nedre Elvehavn area was transformed from disused shipyards and harbor functions into a modern district with commerce and housing around the year 2000, it was decided that Gråmølna should be given to the Trondheim Art Museum, and in 2008 the museum opened a section consisting of the old brick building and a new pavilion designed by Per Knudsen Arkitektkontor AS.