Some areas are looking to make use of their dead forests, which could lead to record setting wooden buildings thanks to a new method for building.
With architects and designers constantly looking for ways to create modern, massive structures that utilize eco-friendly techniques, it should come as no surprise that one way to improve the green factor is to use green materials. And what materials can be more green than wood?
Obviously, wood is no stranger to construction. It has its limits though, especially when developers are building high rise structures several stories tall. There comes a point when the weight is just too much for wood, and stone, concrete, and/or steel are required for structural stability. A new method of processing wood, however, may have found a way around that, which opens the door to a new form of eco-construction using wood to build skyscrapers.
The idea came around when the province of British Columbia, Canada was faced with 44m acres of dead trees – roughly the size of Missouri. The decimation of the trees was due to the mountain pine beetle, an insect no bigger than a grain of rice that cuts off the flow of water and nutrients to trees, eventually killing them. The beetle hasn’t been a major problem in the past as it tends to recede in the cold, but unseasonably warm winters led to a massive outbreak, leaving millions of dead trees.
Left alone, those trees will decay or burn. Either option releases a significant amount of carbon dioxide, enough that it could raise Canada’s entire carbon footprint by as much as 2-percent.
As a result, British Columbia passed the “Wood First Act,” which requires that wood is considered first in all construction projects. That helps, but it alone isn’t enough to make a significant difference compared to the amount of trees that need to be removed. That’s where cross-laminated timber (CLT) comes in.
CLT is a production process that uses layered panels built from thin wooden boards, glued together in alternate orientations. It creates a durable material, and the process can also use beetle-kill pine (BKP) and hide the stained bits. BKP panels are rigid and fire-resistant, enough so that they can replace pre-fabricated concrete panels. They do take as much as six times more wood than traditional framing techniques, but in this case, that’s actually a good thing.
Besides British Columbia, CLT has been in use for the last decade or so, primarily in Europe. A nine-story building in London briefly held the record for tallest wooden building in the world, but it was soon replaced by a 10-story building in Melbourne. The tallest wood building in the U.S. will soon be a 12-story building in Portland, OR, and the current record holder for tallest wooden building is a 174 feet, 18-story building in British Columbia, although it might not hold the record for long.
There are currently plans for a 20-story wooden building in Vancouver, BC, a proposed Swedish tower made of wood that will top 30 floors, and one in London that will top them all. If built, the British wooden structure will reach 34-stories. The current plan is to begin construction within the next few years in order to open in 2023.
Along with the environmental benefits, there are also practical benefits to using wood. Although it might seem somewhat contradictory, wood is actually much more fire resistant than steel and concrete. Wood contains 15-percent more water, and that water needs to evaporate first before the wood actually begins to burn. Wood is also good for creating natural acoustics, it helps maintain a structure’s internal temperature better than alternatives, and it can also be cheaper in the long run – it doesn’t need additional materials like plaster.
Tree covered buildings and structures made to look like vegetation-covered mountains might be the current style of the day, but for builders looking to go truly green, they might want to consider mixing old school materials with new school techniques.