by Web Editor | Aug 17, 2018 | News
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/.
by Web Editor | Feb 10, 2016 | News
Last month we saw cross-laminated timbers installed at the Albina Yard project in Portland. It was the first use of U.S.-produced CLT in a building-wide structural system.
The first level of CLT (4,000 square feet) on Albina Yard went up in fewer than four hours. Last week, the second level was installed by a crew of seven in under two hours. Pretty remarkable, considering the contractor says it would have taken at least twice as many people two days or more to frame the same amount of floor space using traditional methods. Albina Yard is a four-story, 16,000-square-foot creative office project in north Portland. Besides its snazzy design by LEVER Architecture, the project is most notable for being tangible evidence that the U.S. CLT industry is officially off the ground.
There’s been a lot of buzz around CLT and mass timber in general over the past several months in Oregon and around the country — and rightly so. Besides drastically improved speed of construction (and the savings that go with that), mass timber offers significant environmental benefits. This includes tremendous carbon-storing capacity. Half the dry weight of wood is carbon. It got there when the trees were growing and absorbing carbon dioxide from the atmosphere. That carbon remains locked up for as long as the wood remains in use (a nine-story wood structure in China is now 959 years old—nearly a millennium). The new trees planted to replace those that were harvested start the carbon cycle all over again.
According to a quick, back-of-the-napkin calculation, Albina Yard, which is small by commercial construction standards, stores about 80.5 metric tons of carbon. That’s equivalent to offsetting 295 metric tons of CO2 emissions.
A larger Portland mass timber building, Clay Creative (60,000 square feet), stores more than 1 million pounds of carbon. Its total of 457.5 metric tons offsets 1,678 metric tons of CO2 emissions. “An additional 3,574 metric tons of CO2 emissions were avoided by using wood rather than concrete and steel,” says Dr. Jim Bowyer, an expert on the subject at Dovetail Partners, Inc.
From the Oregon Forest Resources Institute: https://oregonforests.org/blog/mass-timber-rising
by Web Editor | Jan 18, 2016 | News
Wood is a go-to material for floors, doors, furniture, and now, a skyscraper—the very first of its kind in the U.S. Construction on Portland, Oregon’s wood high-rise, Framework, is slated to begin this October. The 12-story mixed-use building—a collaboration between local firm Lever Architecture and real-estate developer Project—will be made primarily from timber. Thomas Robinson, Lever Architecture’s founder, says his company is interested in “exploring the relationship between materials, experience, and the environment—how the way we build impacts the way we live and the environment as a whole.”
To highlight the innovative design, the structure will be centered around a visible vertical core and capped with a roof deck framed by wood columns. Flexible, sturdy, and lighter than materials like concrete or steel, timber has a high strength-to-weight ratio. Framework’s design includes cross-laminated wood panels, engineered of stacked lumber, for floors and ceilings, and glue-laminated timber for beams and columns.
Inside, a double-height community space will feature a public exhibition documenting the building’s creation and impact, plus a second-floor garden terrace. Visitors will be able to roam retail spaces on the ground floor, while above there will be five floors of offices and five floors of affordable housing.
The “forest to frame” philosophy behind the building reflects its relationship between urban construction and rural lumber manufacturing. This project creates more opportunities in both industries, which were gravely affected in the recession. “Framework stands as a model for sustainable urban ecology,” says Robinson. And there are copious environmental benefits: Buildings made primarily of wood have significantly lower carbon emissions and use less energy than those made from traditional materials. Earlier this year, the U.S. Department of Agriculture took notice. It solicited designs for a tall wood building competition, and the Framework team won an impressive $1.5 million grant to fund further research and development—the structure is expected to be finished by December 2017.
From Architectural Digest: https://www.architecturaldigest.com/story/first-wood-highrise-building-portland
by Web Editor | Nov 20, 2015 | News
Portland is growing up—adding high-rises, increasing density, and pricing many people out. But two local firms are exploring a state-of-the-art building material that could help solve the city’s affordability problem, create living-wage jobs in rural communities, and help save the planet. It’s wood.
Right now, Portland-based LEVER Architecture and real estate development firm Project^ are designing a 12-story mixed-use wood building in the Pearl District that will be made primarily of a material called cross-laminated timber (CLT).
That’s an unheard of height for wood structures, which top out at six stories in most of the US. And it’s not the project’s only unique attribute. Five of those stories will be affordable housing, something Portland desperately needs.
LEVER and Project^ have partnered with Beneficial State Bank (which owns the property at 430 NW 10th), Albina Community Bank, and the housing agency Home Forward on the development, which they’re calling Framework.
The team’s ideas received national attention: In September, the US Department of Agriculture awarded the project a $1.5 million grant—money that will help alleviate the cost of proving to state and local building authorities that tall wooden buildings can meet safety requirements for earthquakes, fires, and other perils.
From The Portland Mercury: https://www.portlandmercury.com/portland/the-worlds-most-sustainable-high-rise-construction-material-is-wood/Content?utm_source=WIT112015&utm_medium=Email&utm_campaign=WeekInTrees&oid=16991973
