If you love the smell of Christmas trees, there’s a new trend in office construction just for you.
Last week, Oregon became the first state to amend its building code to allow for wooden structures taller than six stories. Wooden structures are gaining popularity with architects and builders in the commercial real estate industry, with ambitious projects sprouting up all over the country. Oregon-based architecture firm Lever proposed a 12-story structure taking advantage of the new rules. In Williamsburg, two mid-rise structures will feature wood beamed construction. Minneapolis boasts “T3,” an office opened in 2016 that claims to be “the largest modern mass timber building in the country.”
Experts say the wooden structures are better for the environment and better for the people working inside. And while you’re still more likely to see concrete than cedar in Manhattan, some architects predict this will be a growing trend in office construction.
The wood used to build these structures isn’t exactly the kind you’ll find at Home Depot. Because the wood beams need to carry a heavy load, architects use what’s called “mass timber.” Essentially, these are pieces of wood that are stacked on top of each other in alternating patterns and glued together, making the beam or slab stronger. This allows builders to use younger, faster growing trees, which makes logging more sustainable.
From an environmental perspective, wood is a superior building material to steel and concrete. “Wood is a carbon sequestration material,” says Darin Reynolds, a LEED-credentialed architect and partner at Cook Fox Architects. “Compare that to concrete structures, which create large amounts of CO2 in their construction. It’s increasingly important, with climate change, to find new ways of building.”
Trees absorb and store carbon, pulling it out of the air and keeping it from being released (unless it’s burned). Creating concrete and steel on the other hand is a carbon intensive process. Fast growth trees, like spruce, offer a sustainable source of building materials, as harvested trees can be quickly replaced.
Albina Yard, from Lever Architecture, is an office development that makes use of cross laminated timber (CLT).
Plus, the wood pieces can be reused in future projects.
“The great thing about a wood structure is that it’s life cycle doesn’t end with one building,” says Reynolds. “At the end of a building’s useful life, you can take that wood and reuse it for other purposes. Once a concrete building ends its life cycle, it all goes to the landfill. There’s not much more you can do with it.”
You might think a wooden high rise is a fire disaster waiting to happen, but Reynolds says the thickness of the wood beams makes them highly fire resistant. The charring of the wood when exposed to fire actually creates a layer of insulation that prevents the fire from spreading and allows the wood to stay structurally sound.
Though their 12-story timber project is currently on hold, Lever Architecture have built other structures using this new wood technology. Albina Yard is a 16,000 square foot office building in Portland, and the first in the country to use domestically-produced CLT, or cross laminated timber. And the growth doesn’t stop there. Legendary firm Skidmore, Owings & Merrill published a study proving the feasibility of a 42-story timber high rise—taller than the tallest tree in the world.
Exposed wood beams offer a glimpse of nature around the office at Lever’s Albina Yard in Portland, Oregon.
Timber high rises still have some tall hurdles to cross before they become common place. Other states have yet to follow Oregon’s lead in changing building codes. But that could change soon. The International Code Council will be voting in the Fall on whether to back a new code that would allow for taller wooden structures. Reynolds says if passed, states that use ICC recommendations for guidance, like New York, could follow Oregon’s lead.
But even with the proper codes in place, there are some impediments to growth. “Part of the challenge is that the contractors that build large, multi-story buildings are not used to using (mass timber),” says Reynolds. “They don’t have the skilled tradespeople who have an understanding of how to use it yet.” There’s also the matter of convincing building owners to buy in. Like any new technology, wooden high rises are more expensive than their concrete counterparts, at least for now. Cost will eventually come down, but in the meantime, it will take an investment.
Reynolds hopes that building owners will keep the tenant experience in mind when considering this cost. Numerous studies have shown that being surrounded by nature can markedly improve our moods and health. Incorporating these elements into interior spaces has been in vogue lately with designers and architects—a trend they call “biophilia.” Employers are increasingly interested in offering their employees health and wellness benefits, both to attract top talent and keep their human resources costs lower. Demand from tenants may put pressure on builders to offer more timber structures, even with an initial higher cost. “The biggest expense for an office tenant is the cost of people’s salaries. If their office environment can increase their performance, reduced sick days, improve their mental acuity, it’s better for the bottom line.”
Photos courtesy of Lever Architecture.