Home / Wood Compare / Cumaru vs Spotted Gum
Professional Comparison · Verified Engineering Data · Updated 19 July 2026
Cumaru VS Spotted Gum
Which wood is better for your project? Scores are computed from the verified figures on each species page — how we score.
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Cumaru
98/100 Library Score
🪵Hardwood🌧Outdoor🔥Low Flame Spread💧Moisture Stable
- Higher durability (EN 350 Class 1 vs Class 2)
- Harder wear surface (Janka 3330 vs 2473 lbf)
- Stronger in bending (MOR 175.1 vs 137.0 MPa)
- Better flame-spread class (Class A vs Class B)
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Spotted Gum
86/100 Library Score
🪵Hardwood🌧Outdoor💧Moisture Stable
- Close second across most categories
- Solid choice where its profile fits the project
Visual comparison
CumaruSpotted Gum
Winner by category
There isn't one universally best wood — there's a best wood for each purpose.
| Category | Winner |
|---|---|
| Durability | Cumaru |
| Stability | Tie |
| Hardness | Cumaru |
| Strength (MOR) | Cumaru |
| Stiffness (MOE) | Cumaru |
| Flame spread | Cumaru |
| Machining ease | Spotted Gum |
| Lightness | Spotted Gum |
Engineering data
| Property | Cumaru | Spotted Gum |
|---|---|---|
| Janka Hardness | 3330WD lbf | 2473WD lbf |
| Density | 0.87WD g/cm³ | 0.85WD g/cm³ |
| MOE | 22.33WD GPa | 20.0WD GPa |
| MOR | 175.1WD MPa | 137.0WD MPa |
| Durability | Class 1 Very Durable | Class 2 Durable |
| Stability | Excellent | Excellent |
| Fire (E84) | Class A indicative | Class B indicative |
| Radial Shrink | 5.3WD % | 4WS % |
| Tangential Shrink | 7.7WD % | 6WS % |
| T/R Ratio | 1.45 | 1.5 |
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 | 🥇 Cumaru | ★★★★★ |
| Exterior cladding | 🥇 Cumaru | ★★★★☆ |
| Flooring / wear surfaces | 🥇 Cumaru | ★★★★★ |
| Furniture / interior joinery | 🥇 Spotted Gum | ★★☆☆☆ |
| Structural / load-bearing | 🥇 Cumaru | ★★★★★ |
Advantages & limitations
Cumaru
Advantages
- Rated for exterior exposure (EN 350 Class 1)
- Very low movement in service
- Hard wear surface, dent-resistant
- Best flame-spread class (E84 Class A, indicative)
Limitations
- Hard on tooling; pre-drilling recommended
- Heavy — consider structure and handling
Spotted Gum
Advantages
- Rated for exterior exposure (EN 350 Class 2)
- Very low movement in service
- Hard wear surface, dent-resistant
Limitations
- Hard on tooling; pre-drilling recommended
- Heavy — consider structure and handling
Recommendation
Choose Cumaru if…
- The project lives outdoors and service life is the priority
Choose Spotted Gum if…
- Its profile matches the application better than a single overall score
Frequently asked questions
Which is more durable, Cumaru or Spotted Gum?
Cumaru — it carries the better EN 350 rating (Class 1 vs Class 2). Lower class numbers mean higher natural durability.
Which wood is better for outdoor use?
Cumaru — outdoor performance combines decay durability with dimensional stability, and it leads on that combination.
Is Cumaru harder than Spotted Gum?
Yes — Janka 3330 lbf vs 2473 lbf.
How we score. Each wood gets a weighted composite of the verified figures shown above: durability 22%, stability 18%, hardness 12%, bending strength 12%, machining ease 12%, stiffness 8%, flame spread 8%, lightness 8%. The Library Score is that composite's percentile rank within our 60-species library — 50 means the library median, 90 means it outperforms nine of every ten species we cover. No price data is scored — cost guidance is qualitative. The score summarises the data; it does not replace judgement about your specific application.