A study published in Nature Communications by researchers at the Yale School of the Environment highlights the climate benefits of replacing traditional building materials like concrete and steel with mass timber, particularly cross-laminated timber (CLT). The research reveals that widespread adoption of mass timber in urban construction could reduce global carbon emissions dramatically — but only if forest management is handled responsibly.

Engineered Wood, Reduced Emissions

The study models several future scenarios and concludes that replacing steel and concrete with CLT in 30% to 60% of new urban buildings between 2020 and 2100 could reduce lifecycle greenhouse gas emissions by up to 39 gigatons of CO₂ equivalent. That’s comparable to a full year of global energy-related CO₂ emissions. Furthermore, the switch could drive the expansion of purpose-grown, intensively managed forests by 36.5 million hectares worldwide — an area the size of Germany — contributing to long-term carbon storage.

Forests as Carbon Banks

Unlike earlier assessments, this research incorporates dynamic land-use modelling via the Global Timber Model (GTM). It shows that increased wood demand due to CLT use can actually lead to afforestation, especially in regions like the US, China, Western Europe, and Canada. Mass timber buildings act as carbon sinks themselves, locking in carbon for decades or even centuries.

Critically, the study challenges outdated concerns that mass timber contributes to deforestation. According to Professor Robert Mendelsohn, the findings confirm that demand is largely met through plantations rather than natural forests, shifting the narrative toward regenerative forest use and climate-smart forestry.

Responsible Design and Policy Needed

While the outlook is promising, the researchers caution that the positive outcomes depend on sustainable land-use policies. Without strong environmental safeguards, expansion of timber plantations could threaten natural forests, particularly in tropical regions. This underscores the need for responsible sourcing and regulatory frameworks that balance carbon goals with biodiversity conservation.

A Timber Future for Sustainable Architecture

The findings strengthen the case for biobased construction and support designers aiming to reduce environmental impact through material selection. For architects and planners, mass timber offers not only structural and aesthetic potential but also a tangible way to contribute to carbon-neutral and circular design strategies.

Further research at Yale will explore how other forest-based solutions like biochar and bioenergy with carbon capture might complement timber construction in achieving negative emissions.

Source: Yale School of the Environment
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