Sustainability has become a core principle of architecture and construction in North America. Winners of the Holcim Awards for Sustainable Construction presented in Chicago show how the leading edge of sustainable design means reaching far beyond “common sense”. Their approaches use proven instruments that are cleverly applied to improve the quality of life. So the world builds better.

The design of “Ingrained Framework” proposes a 12-level building using wood as the principal construction material. Intended for realization in the city of Portland, Oregon, the design recognizes timber as an important local resource, acknowledging the region’s long-standing tradition in wood construction. The project thereby intends to encourage widespread use of a carbon sequestering technology, while strengthening local economies in rural communities by increasing wood building product demand. Though similar structures have been erected in the region, it would be the first all mass timber high-rise in North America, using Cross Laminated Timber (CLT) for all load-bearing structural components, including the building’s stabilizing cores.

Innovation and transferability – Progress

Because high-rise wood structures are not prescriptively allowed in the USA code, the Framework project undertook extensive fire, structural, seismic, and acoustic testing to demonstrate the equivalent performance of steel and concrete. The tests included the first successful two-hour fire rated Cross Laminated Timber (CLT) connection. Results from this performance-based design path will be made public to spur widespread acceptance of tall wood structures in USA building codes. The project demonstrates innovation with respect to mass timber and seismic performance. Framework will have a 40-meter post-tensioned CLT rocking wall core – the tallest in the world – that will resist damage from an earthquake and allow the building to remain occupiable even after a major seismic event.