How to Install Thermally Modified Wood Decking
Get a step-by-step installation guide tailored to your thermally modified wood project.
What type of project is this?
Application Type
Residential
Single-family home or personal use
Commercial (Light-to-Moderate)
Light commercial traffic only
Complete Thermally Modified Wood Decking Installation Guide
Thermally Modified Wood is a popular choice for decking applications, valued for its natural beauty and durability. With a Janka hardness of Varies and density of Varies, it offers good performance for residential and commercial projects. Proper installation is essential to maximize the 20+ years expected lifespan.
Janka Hardness
Varies
Density
Varies
Expected Lifespan
20+ years
Origin
North America/Europe
Step 1: Acclimation & Storage
Stack Thermally Modified Wood boards on-site with spacers between every layer for 5-10 days depending on climate. Keep elevated off the ground, covered with a breathable tarp, and open on all sides for airflow.
Step 2: Framing & Substructure
Use pressure-treated joists at maximum 16" on center. Apply joist tape to all joist tops. Ensure at least 18" of clearance underneath for ventilation. Use stainless steel or galvanized joist hangers throughout.
Step 3: Board Layout & Spacing
Plan your layout for visual balance. Side gaps of 3/16" to 1/4" and end gaps of 1/4" are typical. Stagger end joints by at least 2 joists. Place the most attractive boards in high-visibility areas.
Step 4: Pre-Drilling & Fastening
Pre-drill all fastener holes to prevent splitting. Use stainless steel fasteners for best results. Options include face-screwing, hidden clip systems, or face-screwing with wood plugs. Standard carbide-tipped bits work well.
Step 5: Cutting & End-Sealing
Use a carbide-tipped blade for clean cuts. Seal all cut ends immediately with wax-based end grain sealer — at least 2 coats extending 1" onto the board face. This prevents checking and splitting over time.
Step 6: Finishing
Thermally Modified Wood can be finished with penetrating oil to enhance natural color, treated with a UV-protective sealer, or left to weather naturally to a silver-gray patina. Wait 2-4 weeks after installation before applying any finish.
Step 7: Ongoing Maintenance
Sweep weekly and clean 2-3 times per year. If oiled, re-apply annually. Thermally Modified Wood provides 20+ years of durable service with proper installation and maintenance. Never use salt or chemical de-icers.
Required Tools
- Miter saw with carbide blade
- Drill with carbide bits
- Impact driver
- Level
- Rubber mallet
Materials Needed
- Thermally Modified Wood decking boards
- Stainless steel fasteners
- Joist tape
- End grain sealer