He was raised in wealthy conditions in Villa Arons close to Großer Wannsee southwest of Germany's capital.
Due to cultural assimilation, in 1904 he changed his biblical family name Arons to the German sounding Ahrends, possibly at the same time that he and his siblings converted to Christianity.
[3] Ahrends wanted to study Shipbuilding at Kaiserliche Werft in Kiel but at imperial shipyards any participation of Jews was excluded.
Ahrends left civil services to establish himself as an architect in Germany's capital, where the design of housing estates and single homes were a prosperous and prestigious business.
In 1911-12 his first self-contained project was his own family's home, a cottage in the borough Dahlem, today used as villa of the President of the German parliament.
Later he planned and built numerous residential buildings and housing developments in several boroughs of Germany's capital Berlin.
Between 1927 and 1928 he planned a building in Berlin-Wannsee, which was used by his friend Hans Krüger (1884–1945), a president in the Prussian ministry of agriculture, preserves and forestry.
With reference to William Shakespeare's role play its stage was open to all sides and not longer separated from auditorium.
The school's theater hall was also meant as nationwide training post for role play teachers.
Cubic buildings with flat roofs were depreciatedly called a cigar box fashion by citizens.