ThermoWood® vs. Thermally Modified Wood vs. Advantage Thermal™
Understanding the Differences So You Can Make the Best Choice If you’re wondering what is thermally modified wood, this introduction will help clarify the key concepts.
When it comes to specifying or choosing modified wood products for decking, siding, cladding, or other exterior applications, terms like ThermoWood®, Thermally Modified Wood, and Advantage Thermal™ are often used — but they don’t all mean the same thing. Knowing the difference helps you communicate clearly with architects, builders, and customers — and choose the best product for performance and value. Also, it’s helpful to understand exactly what thermally modified wood is and why it matters.

What Is Thermally Modified Wood?
It refers to wood that has been heated to high temperatures in a controlled environment to change its physical and chemical properties. The result is wood that is:
- More dimensionally stable
- More resistant to decay
- Less prone to movement and moisture issues
- Improved for exterior use without chemical preservatives
This category includes many brands and proprietary processes from different manufacturers. As such, if you are researching what is modified wood, remember that it encompasses a range of wood types and treatments.
In essence:
Thermally Modified Wood = a process category that covers all wood modified by heat treatment.

What Is ThermoWood®?
ThermoWood® is a registered trademark owned by the International ThermoWood Association.
- It identifies wood that has been heat-treated using specific standards and protocols set by the association. This means anyone asking “what is thermally modified wood” should know ThermoWood® is one certified version of it.
- The trademark ensures that wood marketed as ThermoWood® meets those standards for quality and performance.
You can learn more about the ThermoWood® process and standards directly from the International ThermoWood Association here:
👉 https://www.thermowood.fi/
While ThermoWood® is thermally modified wood, not all modified wood is ThermoWood®.
✔️ ThermoWood® = a certified, branded segment within the broader modified wood category. It’s important for anyone searching what is thermally modified wood to know this distinction.

Where Does Advantage Thermal™ Fit In?
Advantage Thermal™ is a specific brand of thermally modified wood available through Advantage Lumber.
- It falls within the Thermally Modified Wood product category and is a clear example when considering modified wood.
- Advantage Thermal™ is a thermally modified wood brand, and AdvantageLumber.com® is a member of the International ThermoWood Association which owns the ThermoWood® trademark.
- Advantage Thermal™ uses a direct supply chain and value-driven approach.
What sets Advantage Thermal™ apart:
- Offered in both Pine and Ash, providing flexibility for appearance and application
- Lower cost compared to many premium thermally modified wood brands
- Better return on investment, especially for large or budget-conscious projects
- Excellent performance for decking, siding, and exterior architectural uses
Explore Advantage Thermal™ products here:
👉 https://buy.advantagelumber.com/collections/advantage-thermal
Quick Comparison: At a Glance
| Feature | Thermally Modified Wood | ThermoWood® | Advantage Thermal™ |
|---|---|---|---|
| Category or Brand | Category | Trademarked Brand | Trademarked Brand |
| Trademark Owner | — | International ThermoWood Association | Advantage Lumber |
| Species Options | Varies | Varies | Pine & Ash |
| Cost | Varies | Varies | Lower cost |
| ROI | Depends on product | Good | Excellent |

The Bottom Line on Modified Wood
- Thermally Modified Wood is the overall category describing heat-treated wood products. When you think about what is thermally modified wood, this category definition is key.
- ThermoWood® is a specific trademarked brand governed by the International ThermoWood Association.
- Advantage Thermal™ delivers the benefits of thermally modified wood with lower upfront cost and stronger ROI, making it an ideal choice for many commercial and residential projects.