Thermally Modified Wood (TMW) is natural wood that has been enhanced through a controlled heat and steam process. This treatment improves the wood’s durability, dimensional stability, and resistance to decay ,all without using any chemicals. In this guide, we’ll explain :
- How thermal modification works
- Key benefits compared to other materials
- Best use cases
- Popular wood species
- Why it’s a sustainable, eco-conscious choice
How is Wood Thermally Modified ?
The thermal modification process involves heating wood to 160–220°C (320–430°F) in a low-oxygen environment. This is done to change the cellular structure of the wood, reducing its ability to absorb water and making it resistant to rot, mold, and insects.
Unlike pressure-treated wood, no harmful chemicals are used , only heat and steam. The result is a durable, stable, and non-toxic product.
Benefits of Thermally Modified Wood :
- Enhanced Durability : TMW lasts longer than untreated wood and resists biological decay.
- Dimensional Stability : Minimized swelling, shrinking, or cupping due to moisture changes.
- No Chemicals : Safe for humans, pets, and the environment . ideal for eco-conscious projects.
- Rich Aesthetic : Beautiful darkened tone throughout the board (not just surface-stained).
- Low Maintenance : Requires little to no chemical treatment over its lifespan.
Where Can Thermally Modified Wood Be Used ?
Thermally modified wood is ideal for :
- Decking & patios
- Marine
- Facades and siding
- Pergolas & gazebos
- Interior walls and ceilings
- Outdoor furniture
- Sauna cladding
It’s not suitable for direct ground contact or underwater use , those require special species (like Iroko , Teak …etc ) .
Popular Species for TMW
- Iroko (African Teak): Naturally durable + modified for extra strength
- European Ash: Stylish light tone, great for decking and siding .
- Scandinavian Pine: Budget-friendly, warm look.
- Ayous (Obeche): Lightweight , thermal insulation and easy to finish , best at Siding .
Each wood species reacts differently to heat, and we choose only certified FSC timber for modification in Jartek kilns.
TMW vs Other Outdoor Materials
| Material | Chemical-Free | Environmentally Friendly | Safe for Children & Pets | Natural Appearance | Long Lifespan |
|---|---|---|---|---|---|
| Thermally Modified Wood | ✅ | ✅ | ✅ | ✅ | ✅ |
| Pressure-Treated Wood | ❌ | ❌ | ❌ | ❌ | ✅ |
| Untreated Wood | ✅ | ✅ | ✅ | ✅ | ❌ |
| Composite (Plastic-Based) | ❌ | ❌ | ❌ | ❌ | ✅ |
Does It Need Special Installation?
No. TMW installs just like traditional wood.
However : Leave spacing for airflow . Use stainless steel screws .
Safe and Certified
- Non-toxic: No outgassing or leaching
- Kid & pet safe: Great for playgrounds and decks
- Certified: FSC certifications
- Meets Class 3 / UC3 requirements for above-ground exterior use (like decks, fences, siding)
Why choose plastic when nature offers better? Thermally modified wood is sustainable, chemical-free, and built to stand the test of time.
FAQ
- Q: Is it waterproof? No, but it’s highly water-resistant.
- Q: Can I use it in soil? Not directly. For ground contact, use UC4 or durable tropical hardwoods.
- Q: Does it fade? Like all wood, it will gray over time in sunlight unless UV protection is applied.
- Q: Can I paint or oil it? Yes. Most people use natural oils to preserve color.
Why Choose PeraWood?
- European kiln technology ( Jartek )
- Made in Türkiye, shipped worldwide
- FSC-certified, chemical-free
- Wide range of profiles and sizes
