Mass Timber Products Take Center Stage in Multi-Story Construction

Governor Brown has declared October 15-21, 2017 as “Oregon Forest Products Week” and asked all Oregonians to join in observance. In her signed proclamation to designate this week, Governor Brown recognizes Oregon’s forest sector as the state’s leading traded sector that contributes more than $12 billion annually to the state’s economy and employs more than 60,000 Oregonians with above-average annual incomes. One sector in the forest products industry that has garnered significant attention in recent years, both domestically and abroad, is mass timber construction. As in so many things sustainable and cool, Oregon is a leader in this industry.

Mass timber construction uses large panelized wood products such as cross-laminated timber (“CLT”) or glue-laminated timber (referred to as “glulam”) instead of concrete and steel. CLT is made by layering pieces of wood panels in alternating patterns that are glued together into massive panels several layers thick, which can be as large as 65 feet by 20 feet, and are strong enough to replace concrete and steel in high-rise buildings. Glulam is made by the same kind of process, but the pieces are aligned in the same direction, which provides increased strength and makes it suitable for the structural components of a building, such as structural beams. Mass timber construction meets all structural, fire and earthquake code requirements, but instead of using resource- and energy-intensive building materials like concrete and steel it uses a renewable resource (trees). The fact that the building is made out of wood means that this form of construction sequesters (or captures) carbon emissions by trapping the carbon dioxide inside the trees which make up the building. WoodWorks, an initiative of the Wood Products Council, has created a carbon calculator that allows users to calculate how much time it takes to grow the wood, the amount of carbon sequestered in the wood products, and the greenhouse gas emissions avoided. Using the example of a building that included 58,481 cubic feet of CLT, the calculator calculates that this amount of CLT can be grown in US and Canadian forests in five minutes, the building will store 1,276 metric tons of carbon dioxide equivalent, and the impact is equal to 374 cars off the road for one year.

Looking around Oregon’s abundance of forests, it is no surprise that Oregon is home to a robust forest products industry. In fact, Oregon is home to the United States’ first producer of APA-certified CLT, D.R. Johnson in Riddle, Oregon, and the United States’ largest glulam producer, Rosboro in Springfield and Veneta. Currently underway in Hillsboro is the construction of a five-story building with 156,000 square feet of office space made out of CLT for flooring and glulam for posts and beams. This building will house First Tech Credit Union’s headquarters. Scheduled for construction in 2018 is a 12-story building called Framework (pictured above), which will be built in the Pearl District and, at 148 feet tall, will be the tallest wood building in the United States. The building is partially funded by a prize through the US Department of Agriculture’s Tall Wood Building Prize Competition. The building will house a bank and timber exhibit at ground level, and offices and affordable housing above, along with a roof deck and garden.

To learn more about mass timber construction, you can check out the World Forestry Center’s new exhibit called The Future of Tall, or attend the International Mass Timber Conference in March 2018, which has been hosted in Portland since 2016 and brings in speakers from all over the world. .

Framework Rendering by Lever Architecture.