News that an outpost of the fast-food eatery in Chicago is being built with mass timber serves as the proof in the proverbial pudding that a sustainable building approach already popular in Europe and Canada is on the verge on breaking through to the mainstream in America. Wood is officially having a moment.

Noted for its strength, beauty and low-carbon footprint, wood has been used as a building material for eons. But modern mass timber construction, which includes engineered wood panel products such as cross-laminated timber (CLT) and nail-laminated timber (NLT), is still a relatively new concept in the United States. At its most basic, the term “mass timber” describes projects that use solid or engineered wood as a primary structural element, from the flooring to the roof to the load-bearing walls.

The new McDonald’s, a global flagship location, will be the first CLT structure in the Windy City. In describing CLT, Carol Ross Barney of Ross Barney Architects, the firm behind the building, told Curbed, “One way to think about it is plywood on steroids.” She also noted, “CLT is versatile, and because the wood can be harvested and renewed at a more regular interval, it has a relatively low carbon footprint.”

The McDonald’s aside, it’s the possibility of reaching once-unthinkable heights that’s really propelling the mass timber movement forward. Often referred to “tall wood” buildings, mid- and high-rise timber towers have been topped off, or are in the works, in cities across the globe, from Paris to Melbourne to Stockholm to Vancouver, B.C. While stateside enthusiasm for towers that eschew concrete and steel in favor of engineered wood is strong, outdated local building codes often stand in the way.

That might soon change. As reported by Building Design + Construction magazine, a recent move to update codes for timber construction by the International Code Council (ICC) could pave the way for bigger, better and taller mass wood projects. In the United States alone, 35 pending timber tower projects, ranging in height from seven to 24 stories, could potentially get the go-ahead in the coming months. Already, a slew of mass wood structures stretching up to 18 stories has been approved in places such as Norway, Canada and the United Kingdom.

The much-heralded T3 building in Minneapolis, completed in 2016, goes to show that thinking big in the realm of modern mass wood construction can yield innovative, gorgeous and environmentally friendly results. Sprawling across 220,000-square-feet and rising seven-stories tall, T3 is the largest modern mass timber building in the United States.

Constructed from more than 1,000 NLT panels engineered from wood sourced from trees killed by mountain beetles, it’s a thoroughly contemporary building. Yet this high-performance commercial office complex is also a bit of a throwback; the structure is designed in such a way that it melds seamlessly into the surrounding urban landscape dominated by landmark early 20th century warehouses.

While not as substantial in terms of square footage as T3, Carbon12, a sleek, solar panel-topped residential tower in Portland, Oregon, claims to be the tallest mass timber structure in the United States. Completed in late 2017, it rises 85-feet (eight stories) above downtown Portland and, like T3 in Minneapolis, it both trumpets and pays homage to the local lumber industry.

Mass timber still has its challenges in the United States. Tariffs on softwood lumber imports from Canada could potentially drive up costs. A 12-story mass timber building project in Portland, Oregon, for which the city and state granted permits in 2017, was recently put on indefinite hold by the developer for financial reasons, including fluctuations in the tax credit market.

But with the relaxation of building codes and the drive to leave a cleaner, greener planet for future generations, the sky may ultimately be the limit for tall wood.

Based in New York City, Matt Hickman writes about cities, sustainable design and the intersection between the natural world and the built environment.

Image Credit: Courtesy of Ross Barney Architects