Mass timber could reduce construction industry emissions by up to 25%
The buildings in which we live and work are contributing to the climate crisis. The construction industry is responsible for nearly 16% of the world’s carbon dioxide emissions, mainly from the production of steel and concrete. These materials are essential for today’s infrastructure, but they come with a huge environmental cost. Some developers believe switching to mass timber—a modern version of engineered wood—could help reduce these emissions. But while the idea has potential, experts say it’s far from a perfect solution.
Mass timber is promoted as a cleaner alternative to steel and cement. Advocates claim it could cut construction industry emissions by up to 25%. But the reality is more complicated. Mass timber still produces emissions and can contribute to deforestation, and it comes with trade-offs that may limit its long-term effectiveness.
Mass timber, sometimes called “massive timber,” is not the same as the planks you find at the hardware store. It’s an engineered wood product made by gluing, pressing, or pegging layers of lumber together to form large structural pieces like beams, columns, and panels. This makes the material strong enough to support tall buildings, rivalling steel in some applications.
Several types of mass timber exist:
- Cross-laminated timber (CLT): Layers of wood are stacked at right angles and pressed together.
- Laminated veneer lumber (LVL): Thin wood layers are stacked and glued like plywood.
- Dowel-laminated timber (DLT): Wooden dowels hold layers together, no glue required.
- Nail-laminated timber (NLT): Nails are used to bind stacked boards.
In all cases, a fire-resistant coating is added to protect the structure.
Because mass timber is lighter than steel and concrete, buildings made from it can be quicker and cheaper to construct. It also locks carbon into the structure for decades, which appears to be a win for the planet.
Using wood instead of steel or concrete can reduce emissions because trees absorb carbon dioxide while they grow. If turned into mass timber, that carbon remains stored, as long as it does not burn or otherwise degrade.
Unlike cement, which is made by heating limestone in kilns that run on fossil fuels, and steel, which relies on high-temperature furnaces, mass timber doesn’t need such energy-intensive processes. That’s why some construction firms are betting on wood to lower their construction industry emissions.
And the numbers are tempting. According to several reports, using mass timber instead of conventional materials could cut emissions from the construction industry by around 25%. Such a reduction would be a significant step toward achieving global climate goals.
Despite its promise, mass timber has environmental drawbacks that often get overlooked. First, the act of cutting down trees for timber releases carbon that would otherwise stay locked in forests, because most of a tree doesn’t end up in the final product. Only about one-third of the wood from each tree becomes usable lumber. The rest becomes waste or is used for lower-grade products.
Additionally, once a tree is cut down, it can no longer produce oxygen. While mass timber buildings can last 60 to 100 years, living trees can trap carbon and produce oxygen for centuries. This difference matters when calculating the long-term impact of switching from concrete and steel to wood.
According to the World Resources Institute, many mass timber advocates ignore or downplay the emissions from logging, transporting, and processing trees. They also tend to use overly optimistic data about sustainable forestry practices.
There’s another problem: forests can’t keep up with the demand. Growing trees takes decades, and forests already face enormous pressure from agriculture, wildfires, and development. If the construction industry significantly increases its use of timber, it could lead to even more deforestation, especially in countries without robust forest protections.
Some developers propose using tree plantations to supply the wood. These are fast-growing, single-species forests planted specifically for timber production. While plantations can ease pressure on natural forests, they also create problems. They often replace diverse ecosystems and sometimes displace communities that rely on forest lands for their livelihoods.
If the world continues on its current path, we could lose forest cover equivalent to the entire contiguous United States by 2050. Increasing timber harvests could accelerate this trend.
That doesn’t mean mass timber has no role in climate solutions. It can reduce construction industry emissions significantly compared to traditional materials and offers design flexibility. It also gives buildings a warmer, more natural feel.
However, experts agree that it’s not a silver bullet. To make a serious impact on climate goals and construction industry emissions, we’ll also need cleaner versions of steel and concrete. Companies are already working on low-emission alternatives using recycled materials, electric furnaces, and new types of cement.
If mass timber is used, it should be part of a larger strategy that includes better forest management, stricter regulations, and innovative materials. Builders, architects, and policymakers will need to weigh all the trade-offs to make informed decisions that benefit the planet.
Building with mass timber also changes the way crews work. Unlike steel or concrete, timber components are often prefabricated off-site and assembled quickly on location. This shift can enhance worker safety by reducing the time spent on scaffolding or in hazardous environments.
However, it also means that builders need new training and tools. Construction workers, engineers, and safety inspectors all need to learn how to handle this newer material. Schools and unions will need to catch up to ensure workers are adequately prepared.
On the positive side, this shift can lead to more specialized jobs and potentially higher wages. It can also reduce workplace accidents—something that benefits everyone in the industry.
Whether you’re renting an apartment, buying a home, or working in a downtown office, construction industry emissions affect your daily life. The materials used in your surroundings shape the air you breathe and the climate you live in.
Lowering emissions from the construction sector will reduce pollution, slow climate change, and make cities more sustainable. While you may not have a choice in your building materials, you can still support responsible development by backing eco-friendly housing policies and staying informed about sustainable building practices.
The future of construction will likely involve a mix of materials—some old, some new—all aimed at reducing emissions and protecting the planet.
