What is the Difference Between Sawnwood and Thermowood?
The Heat Treatment Revolution: Sawnwood vs Thermowood Explained
“What exactly is thermowood?” This question comes up daily at our showroom. It represents one of the biggest innovations in timber treatment we’ve seen in years. Let’s break down what makes these two options different and when each makes sense.
Understanding Sawnwood
Sawnwood is timber in its natural state after being cut. It retains all natural characteristics – both good and challenging.
Characteristics:
- Natural wood color and grain
- Standard moisture behavior
- Traditional workability
- Natural oils intact
The Thermowood Innovation
Thermowood undergoes controlled heat treatment at 160°C to 230°C in reduced oxygen conditions. This modifies the wood’s cellular structure permanently.
The Process:
- Initial heating to 100°C with steam
- Heat treatment at 160-230°C for 2-4 hours
- Gradual cooling with moisture reintroduction
- Final moisture content: 4-7%
Key Differences That Matter
Moisture Stability – The Game Changer
Heat treatment reduces moisture absorption by 40-60%.
Sawnwood: Expands/contracts with seasons, requires regular maintenance Thermowood: Much more stable, fewer gaps, less warping
Durability
Heat treatment destroys nutrients that fungi need.
Sawnwood: Relies on natural resistance (varies by species) Thermowood: Enhanced rot resistance, lasts 2-3 times longer outdoors
Appearance
Sawnwood: Natural species color Thermowood: Develops rich, darker tones permanently
Weight
Thermowood: Typically 5-12% lighter while maintaining strength
Real-World Performance
From our Bangalore projects:
Outdoor Decking:
- Sawnwood: Annual maintenance, gaps after monsoon
- Thermowood: Minimal movement, 2-3 year maintenance intervals
Exterior Siding:
- Sawnwood: Paint failure in 2-3 years, shrinkage gaps
- Thermowood: Longer-lasting coatings, fewer issues
Thermopine
Cost Reality
Initial Investment: Thermowood costs 20-40% more Long-term: Reduced maintenance often justifies premium over 10-15 years
Making Your Decision
Choose based on:
- Performance expectations
- Maintenance tolerance
- Budget considerations
- Environmental conditions
Thermowood offers genuine performance improvements for specific applications. Understanding when it provides value helps you make better material decisions. Also, note that not all species are subjected to Thermo treatment.
Curious about the difference? Visit our showroom where we have sawnwood and thermowood samples of the same species for direct comparison.
