Timber
Just the other day in my materials class, we talked about wood. Wood has been around since before humankind, but it has survived the test of time and is now making a comeback. Many architects, engineers, designers, and contractors are now looking at wood as a feasible building material, but it wasn’t always this way.
From the beginning of time, humans have been using wood for construction. The earliest wooden structures date back to 7000 B.C. as wood was the primary material that humans could effectively and efficiently manipulate to construct shelters. As time went on, the ancient Egyptians, Mesopotamians, Greek, and Romans branched out using different materials as some did not have plentiful access to natural forests nearby. Leading to structures made of stone, earth, and even marble, each society learned how to better control the shape of the materials they were using. With the further evolution of humans and construction techniques, the library of what we could use grew; however, wood remained on the table as a cheap and easy material to use.
Although wood is an incredible material for building, its history has always been scorched with fire. Looking at some of the worst fires, one of the earliest dates back to 64 A.D. when a great fire ripped thought the city of Rome. London has also been through two mass fires, first in 1212 and again in 1666. Of all the major city-wide fires, one of the most notorious was the Great Chicago Fire in 1871. Thanks in part to all these horrific events of history, wood has slowly made its way into the shadows because of its safety concerns. Many structures have looked to iron, cement, steel, concrete, and other high strength materials in order to build taller, stronger, and further.
An artist’s depiction of the Great Chicago Fire in 1871
Even with its bad reputation, wood is now making its way back into the spotlight thanks to recent advancements in research, engineering, and understanding. The industry has employed multiple ways to manipulate wood, ranging from cutting, gluing, nailing, and even lengthening. Cross Laminated Timber (CLT) uses thin sheets of wood and glues them together with the grain alternating to create large prefabricated facades to make construction and assembly more time efficient. Nail Laminated Timber (NLT) takes beams of wood and nails them together on their long faces to make an even larger and stronger beam of wood. Glu-Laminated Timber (GTL) similarly takes thin segments of wood with the grain all going in the same direction and gluing them together, sometimes even in curves, to make structural beams. All these ways and more are just a few methods the industry is using to create even stronger engineered wood. What’s more valuable is that these new versions of wood have fire protection integrated into them. When a fire hits one of these surfaces, it chars on the exterior, protecting the wood at the core; therefore, able to maintain its load bearing capacity. Most of these lumber structural beams can withstand the blaze of fires for 30 minutes to 2 hours, all while burning at an incredibly predictable pace.
The curved Glu-Laminated Timber beams spanning the Richmond Olympic Oval in Richmond, Canada
As the construction industry takes notice of the innovation in engineered lumber, it is also urging its suppliers to do the same. The production of these wood products takes a fraction of the overall energy to manufacture them than it does concrete and steel. When seeing the world moving to more renewable building materials, it gives me a sense of hope for the future. The industry of building structures can be so wasteful in production and construction practices, its good to see that they are moving away and taking advantage of better, more sustainable alternatives. Projects all over the world are taking on the concept of timber construction and challenging the material every step of the way. It seems that wherever I look, I find thrilling new projects that include mass-timber framing. I look forward to seeing what the future will bring for wood, whether it be the wide spread use of engineered timber, or taller and greater wooden skyscrapers.