Mortenson's Mass Timber Zero Carbon Building at WWU Cuts Embodied Carbon 79%

Mortenson completed Kaiser Borsari Hall at Western Washington University, a four-story electrical engineering and computer science facility built with mass timber. The project achieved Zero Carbon and Zero Energy certification from the International Living Future Institute after meeting operational performance requirements. The all-electric building uses CLT panels and glulam members, cutting embodied carbon by 79% compared with a conventional baseline, and reached an energy use intensity of 33.58 kBtu per square foot per year, slightly above its 31 kBtu target but still well below typical lab buildings. A key decision was relocating the electrical room from a planned basement to the first floor, which eliminated the basement, saved over $2 million, and avoided 226 tons of embodied carbon. The project also sourced timber within 600 miles, used prefabrication to cut construction time by 25%, and connects to an existing facility to reduce the new building's footprint by 60%. PV panels cover 75% of the roof, with the rest of the electricity supplied through Puget Sound Energy's Green Direct program. This is a useful case study for owners weighing structural material choices against both budget and carbon goals.