ThermoWood Pine Thermo-D VS ThermoWood Spruce Thermo-D
- Harder wear surface (Janka 540 vs 380 lbf)
- Easier to machine and fasten
- Solid choice where its profile fits the project
Visual comparison
Winner by category
There isn't one universally best wood — there's a best wood for each purpose.
| Category | Winner |
|---|---|
| Durability | Tie |
| Stability | Tie |
| Hardness | ThermoWood Pine Thermo-D |
| Strength (MOR) | ThermoWood Spruce Thermo-D |
| Stiffness (MOE) | ThermoWood Spruce Thermo-D |
| Flame spread | Tie |
| Machining ease | ThermoWood Spruce Thermo-D |
| Lightness | Tie |
Engineering data
| Property | ThermoWood Pine Thermo-D | ThermoWood Spruce Thermo-D |
|---|---|---|
| Janka Hardness | 540UNV lbf | 380UNV lbf |
| Density | 0.42ITWA g/cm³ | 0.42ITWA g/cm³ |
| MOE | 9.3ITWA GPa | 10.1ITWA GPa |
| MOR | 38.1ITWA MPa | 47.5ITWA MPa |
| Durability | Class 2 Durable (treated) | Class 2 Durable (treated) |
| Stability | Moderate | Moderate |
| Fire (E84) | Not classified | Not classified |
| Radial Shrink | 1.2ITWA % | 1ITWA % |
| Tangential Shrink | 2.5ITWA % | 2.2ITWA % |
| T/R Ratio | 2.08 | 2.2 |
Figures carry the same source status as the species pages they come from — verified where cited, indicative where marked.
Best for
| Application | Recommended | Suitability |
|---|---|---|
| Outdoor decking / pergola | 🥇 ThermoWood Pine Thermo-D | ★★★☆☆ |
| Exterior cladding | 🥇 ThermoWood Spruce Thermo-D | ★★★★☆ |
| Flooring / wear surfaces | 🥇 ThermoWood Pine Thermo-D | ★★☆☆☆ |
| Furniture / interior joinery | 🥇 ThermoWood Spruce Thermo-D | ★★★☆☆ |
| Structural / load-bearing | 🥇 ThermoWood Pine Thermo-D | ★☆☆☆☆ |
Advantages & limitations
ThermoWood Pine Thermo-D
Advantages relative to ThermoWood Spruce Thermo-D
- Janka is 540 lbf vs 380 lbf, about 42% harder
Limitations relative to ThermoWood Spruce Thermo-D
- MOR is 38.1 MPa vs 47.5 MPa, about 20% lower
ThermoWood Spruce Thermo-D
Advantages relative to ThermoWood Pine Thermo-D
- MOR is 47.5 MPa vs 38.1 MPa, about 25% higher
Limitations relative to ThermoWood Pine Thermo-D
- Janka is 380 lbf vs 540 lbf, about 30% lower
Recommendation
Choose ThermoWood Pine Thermo-D if…
- Saunas (a signature use — low thermal conductivity and no resin bleed after modification) where the sauna-specific profile is the specification
- Exterior cladding and decking where the higher hardness matters in service
Choose ThermoWood Spruce Thermo-D if…
- Exterior cladding and rain screens, decking and sauna interiors where the higher bending strength matters in specification
- Garden structures, interior panelling and ceilings where the modified spruce profile is what the project is specifying
Frequently asked questions
Which is more durable, ThermoWood Pine Thermo-D or ThermoWood Spruce Thermo-D?
Neither — both carry the same EN 350 rating (Class 2, Durable (treated)). Outdoors, movement will not separate them either — 2.5% against 2.2% tangential. Weight is a wash — both sit at 0.42 g/cm³, so freight and overhead handling are comparable and the pick comes down to hardness and bending strength.
Which wood is better for outdoor use?
Both are EN 350 Class 2, and tangential movement runs 2.5% for ThermoWood Pine Thermo-D against 2.2% for ThermoWood Spruce Thermo-D — close enough that decay resistance will not choose between them, and ThermoWood Spruce Thermo-D holds its dimension marginally better. ThermoWood Pine Thermo-D gives the harder wearing surface at 540 lbf; both sit at 0.42 g/cm³ so weight is not what separates them — hardness for traffic, bending strength for cladding and spans.
Is ThermoWood Pine Thermo-D harder than ThermoWood Spruce Thermo-D?
Yes — Janka 540 lbf vs 380 lbf.