Project: A protective roof over a spring water source in Jilin province, China architect Jensen & Skodvin architects Ellefsen, Karl Otto Heftet / 2018 / Engelsk
Project: The Oslo School of Architecture and Design (AHO) architect: Jarmund / Vigsnæs Architects Ellefsen, Karl Otto Heftet / 2018 / Bokmål
Project: Two summer houses, architect: Arne Henriksen arkitekter Ellefsen, Karl Otto Heftet / 2011 / Engelsk
Project: A protective roof over a spring water source in Jilin province, China architect Jensen & Skodvin architects Ellefsen, Karl Otto Heftet / 2018 / Engelsk
Project: Østfold University College, architect: Reiulf Ramstad arkitekter Ellefsen, Karl Otto Heftet / 2010 / Engelsk
Project: Two summer houses, architect: Arne Henriksen arkitekter Ellefsen, Karl Otto Heftet / 2011 / Engelsk
Project: Moholt student village, architect: MDH arkitekter Groba, Ute Christina Heftet / 2023 / Engelsk
Project: Wesselkvartalet, architect: Vigsnæs+Kosberg++Arkitekter Skodvin, Børre Heftet / 2023 / Engelsk
Project: Military training facility, architect: Longva arkitekter Ellefsen, Karl Otto Heftet / 2017 / Engelsk