A/S Trevaren in Lærdalsøyri was launched on 1922 by Anders H Aarethun Per Lem, Severin Gullaksen and Elling Hovland.
In the beginning the factory rented premises in "Habben" and has from the start produced windows, doors and a varied selection building articles
A / S Trevaren also produced style furniture in the interwar period, and a time also coffins.
From late 1970 century  A/S Trevaren also started as a building contractor and had in 2008 a turnover of 130 million.
A / S Trevaren owned by brothers Arvid Magne and Erik Magnus Aarethun which owns 50% each
Trevaren currently has its largest turnover in it's  Entrepreneur department and is involved in many projects, both in Western parts of Norway and the central mountain area.

In November 2012 A/S Trevaren celebrated  it's 90 year anniversary