Wooden walls can withstand 100 kilonewtons of pressure, research finds

Swiss researchers at Empa, led by PhD student Nadja Manser, have demonstrated through large-scale experiments that timber frame walls containing window openings can withstand horizontal loads exceeding 100 kilonewtons. This finding challenges the longstanding engineering assumption that windowed timber walls provide little to no structural support and are treated as voids in design models. The research, conducted in collaboration with ETH Zurich and Bern University of Applied Sciences, involved testing full-scale two-story timber walls under controlled lateral pressure until failure, revealing that such walls contribute significant bracing capacity. This breakthrough addresses a critical gap in timber engineering regulations, which currently lack guidelines for horizontal load-bearing in walls with window openings. Manser is now developing a computational model to accurately capture the horizontal stiffness of these walls, enabling engineers to predict wall behavior under lateral loads without relying on overly conservative assumptions. The research suggests that in some buildings, the need for concrete cores to achieve stiffness might be reduced or eliminated, potentially leading to more efficient and sustainable timber construction