Oregon Becomes First State To Legalize Mass Timber High Rises

Thanks to a recent addendum to Oregon’s building code, the state is the first in the country to allow timber buildings to rise higher than six stories without special consideration.

Portland has become something of a hotbed for timber innovation as of late. Carbon12, PATH Architecture’s eight-story glulam and cross-laminated timber (CLT) tower with a steel core, recently became the country’s tallest timber building and was set to be surpassed by LEVER Architecture’s 12-story Framework. Alas, that project was put on hold due to mounting financial difficulties last month, but it seems the precedent that the project achieved in securing a building permit from the State of Oregon and City of Portland will live on.

The timber allowance comes courtesy of Oregon’s statewide alternate method (SAM), a state-specific program that allows for alternate building techniques to be used after an advisory council has approved the “technical and scientific facts of the proposed alternate method.” The allowance comes after the International Code Council (ICC)–the nonprofit group that Oregon models its building codes after–established the ICC Ad Hoc Committee on Tall Wood Buildings in 2015 to explore the benefits and challenges of using timber in tall buildings.

A Committee Action Hearing was held in April of this year, where the Ad Hoc Committee, made up of code experts, stakeholders, and industry members presented their findings. All 14 of the committee’s suggestions were adopted, introducing standards and best practices for fireproofing, the load-bearing potential of CLT and heavy timber, water resistance, sealing, seismic ratings, and more.

Three new building classifications were introduced as a result: Type IV A, timber buildings permitted up to 18 stories and 270 feet tall, Type IV B, timber buildings with a maximum height of 12 stories and 180 feet, and Type IV C, which is permitted to rise nine stories and 85 feet tall at maximum. The shortest of the timber typologies is allowed to use exposed structural timber as an interior finish, whereas the tallest, type A, must enclose all exposed surfaces and include a three-hour fire-resistance rating for the structural elements.

Read more on this from The Architects Newspaper at https://archpaper.com/2018/08/oregon-legalize-mass-timber-high-rises/.

Oregon Researchers Tout Potential Of New Engineered Wood

Oregon wood researchers hope to bring a new type of engineered lumber to market after tests to make sure it meets state building codes. Oregon State University has been notified that it will receive a $447,000 grant from the federal Economic Development Administration for the testing of cross-laminated timber, or CLT.

The testing will allow the development of manufactured wood products that meet state building codes so the products can be approved for the construction of large buildings, said Geoff Huntington, director of strategic initiatives for OSU’s College of Forestry.

“Our objective is to make CLT and other innovative uses of mass timber products technically feasible, economically viable and accessible alternatives for architects and developers seeking to use Oregon products to meet growing consumer demand for healthy, sustainable buildings,” he said. Plans for Oregon’s first cross-laminated timber buildings already are on the drawing boards.

CLT is composed of large wooden panels made with hundreds of pieces of wood, typically 2-by-4s or 2-by-6s laid perpendicular and glued together, Huntington said. The wooden panels are large, ranging from 10-feet-by-20-feet to 20-feet-by-40-feet. They can be used for walls, ceilings and floors, typically in buildings several stories tall, he said.

The product has been used in multistory buildings in Europe and Canada for several years, but the engineered wood hasn’t been approved for construction purposes in the United States, Huntington said.

From The Register-Guard: https://registerguard.com/rg/news/local/34077270-75/oregon-researchers-tout-potential-of-new-manufactured-wood-in-building-industry.html.csp