Carbon-Conscious Construction: Thermally Modified Hardwood for a Low-Emission Future

The construction industry accounts for nearly 37% of global energy-related CO₂ emissions (UNEP & GlobalABC, 2022). While much of the focus has been on creating energy-efficient building operations, there is growing recognition that embodied carbon – the emissions from producing and maintaining building materials – should also be addressed. This movement has led architects and builders to increasingly seek natural, durable materials that can both store carbon and withstand the test of time.

An increasingly recognized solution is thermally modified hardwood, which becomes more durable, stable, and weather-resistant through heat treatment—without chemicals—making it ideal for low-emission building design. At Jartek, we have witnessed how the combination of hardwood and advanced thermal modification technology can deliver both performance and support sustainable efforts.

Beyond Harvest – Carbon and the Lifespan of Wood
Wood is unique among construction materials; it is carbon-negative at the point of harvest, storing atmospheric CO₂ captured during tree growth. That carbon remains locked in as long as the material is in use.

Durability is central to this benefit. Exterior hardwood, for example, can last 10–15 years before replacement is needed—each replacement bringing new emissions from harvest, manufacturing, and installation. Extending service life, therefore, directly reduces a building’s long-term embodied carbon footprint.

Untreated vs. Thermally Modified Hardwood: A Lifecycle Perspective
Thermal modification means that wood’s structure is altered at the molecular level using heat and steam. The result of the thermal modification process is a material that exhibits improved decay resistance and dimensional stability, making it suitable for demanding outdoor conditions. There is a significant difference between the carbon performance of untreated versus thermally modified hardwood. In an outdoor setting, untreated hardwood will likely require at least one complete replacement within the lifespan of a building. Thermally modified hardwood, on the other hand, may last the whole period of a building’s lifespan – and often beyond – with minimal maintenance. Due to its extended lifespan, thermally modified wood effectively reduces the carbon cost per year of service and additionally cuts any emissions associated with manufacturing, transportation, and maintenance.

Another factor supporting the use of thermally modified hardwood is the process itself, which involves no chemicals, ensuring that the wood remains safe for reuse or energy recovery at the end of its lifecycle. This factor also aligns with the principles of a circular economy system—where resources are kept in productive use for as long as possible and materials are disposed of in ways that prevent further environmental harm.

Jartek’s Expertise: Precision, Consistency, Sustainability
Maintaining uncompromising quality while refining the process on an industrial scale has been the key to Jartek’s market position as one of the world’s leading suppliers of thermal modification technology. By exercising precise process control and achieving consistent results that meet demanding performance specifications, Jartek chambers embody the Finnish engineering heritage that underpins every chamber designed and manufactured.

Focusing on energy efficiency within the process itself is also important to us. Using heat recovery systems and optimized cycles help lower the environmental footprint of the process. Reliable performance with reduced production-related emissions can be critical for hardwood producers and building project partners alike in their pursuit of meeting modern sustainability goals and various green building certifications.

Building for a Low-Carbon Future
Thermally modified hardwood gives NHLA members a powerful story to share with architects and builders: a material that avoids chemical additives, supports circular economy principles, and delivers natural beauty while lowering embodied carbon. By offering products that align with today’s sustainability standards and design trends, members can not only meet market expectations but also strengthen hardwood’s reputation as the premier low-emission building material. Long-term material performance is becoming increasingly important as the market shifts towards solutions that address not only operational efficiency but also meet the growing demand for greener building practices.

The path to carbon-conscious construction is clear: buildings must be designed with both operational and embodied emissions in mind. At Jartek, thermally modified hardwood is the cornerstone of this approach. By combining the natural advantages of hardwood with our advanced thermal modification technology, we deliver a product that performs, lasts, and supports sustainable initiatives.

Thermally modified hardwood can therefore be seen as more than a technical upgrade – it is a commitment to a lower-carbon, higher-quality built environment. For forward-looking architects and builders, thermally modified wood is a material choice that delivers today and endures for the years to come.

Source citation:
UNEP & GlobalABC, Global Status Report for Buildings and Construction (2022) — “In 2022, buildings were responsible for 34% of global energy demand and 37% of energy and process-related carbon dioxide (CO₂) emissions.”