U-value

Gustavsen, Arlid, Bjørn Petter Jelle, Dariush K Arasteh, and Christian Kohler. State-of-the-Art Highly Insulating Window Frames - Research and Market Review. Olso: INTEF Building and Infrastructure, 2007.

Gustavsen, Arlid, Goce Talev, Dariush K Arasteh, Howdy Goudey, Christian Kohler, Sivert Uvsløkk, and Bjørn Petter Jelle. "Experimental and Numerical Examination of the Thermal Transmittance of High Performance Window Frames." Thermal Performance of the Exterior Envelopes of Whole Buildings XI International Conference, December 5-9, 2010. Clearwater Beach, FL, 2010.