He was born at Strandbråten in Sigdal as a son of smallholders Helge Eileifson Kolsrud (1846–1911) and Kjersti Steffensen (1845–1898).
He graduated from Asker Seminary in 1894, and was hired as a school teacher in Nes, Buskerud in the same year.
From 1930 to 1939 he was a board member of the Norwegian School Inspector and Manager Association (Norges Skoleinspektør- og Bestyrerforening).
From 1912 to 1922 he was a board member of Møre Fylkes Ruteselskap, a company that ran the boat and ferry traffic in mid-Norway.
From 1908 to 1910, he also chaired the regional branch of Det Norske Totalavholdsselskap, the oldest temperance organization in Norway.