Grashoff studied civil engineering at Delft University of Technology. From 1983 to 1984 he was a member of the National Students Trade Union. He worked as a civil engineer before becoming a full-time politician.
From 1998 to 2006 he was an alderman of the municipality of Delft, where his responsibilities included transportation. From 2008 to 2010 he was an alderman of the municipality of Rotterdam. His responsibilities included culture and participation.
On 6 June 2018, Grashoff announced he would resign as member of the House of Representatives.[2]
Underline signifies the parliamentary leader (first mentioned) and the Speaker Angle brackets signify a replacement member or a member who prematurely left this House of Representatives