Her area of work is concentrated on East Frisia, the Oldenburg Land and the Wesermarsch.
She learned organ building in the 1970s at the Werner Bosch Orgelbau [de] company (Kassel) and Rudolf Janke and was a journeywoman with Gerald Woehl until 1984 (Marburg), with whom she also took the master craftsman's examination (1990).
From 1985 to 1991, she led the "Krummhörner Orgelwerkstatt" in Greetsiel, a collective of young organ builders (Bartelt Immer, Hero Bödeker, Martin and Wilfried Fooken).
After passing his master craftsman's examination in 1995, he worked in their workshop from 1996 to 2000, specialising, among other things, in the construction of chest organs.
Stegemann continued to use the workshop for her own organ building projects and was a temporary employee in his business until Koop's death in June 2014.