Home / Wood Compare / Douglas Fir vs Sweet Chestnut
Professional Comparison · Verified Engineering Data · Updated 19 July 2026
Douglas Fir VS Sweet Chestnut
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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Douglas Fir
66/100 Library Score
🌲Softwood💧Moisture Stable
- Stronger in bending (MOR 85.0 vs 71.4 MPa)
- Easier machining and fastening (lower density/hardness)
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Sweet Chestnut
51/100 Library Score
🪵Hardwood🌧Outdoor💧Moisture Stable
- More durable (Class 2)
- Solid choice where its profile fits the project
Visual comparison
Douglas FirSweet Chestnut
Winner by category
There isn't one universally best wood — there's a best wood for each purpose.
| Category | Winner |
|---|---|
| Durability | Sweet Chestnut |
| Stability | Tie |
| Hardness | Tie |
| Strength (MOR) | Douglas Fir |
| Stiffness (MOE) | Douglas Fir |
| Flame spread | Sweet Chestnut |
| Machining ease | Douglas Fir |
| Lightness | Douglas Fir |
Engineering data
| Property | Douglas Fir | Sweet Chestnut |
|---|---|---|
| Janka Hardness | 620WD lbf | 680WD lbf |
| Density | 0.48FPL g/cm³ | 0.56WD g/cm³ |
| MOE | 13.4FPL GPa | 8.61WD GPa |
| MOR | 85.0FPL MPa | 71.4WD MPa |
| Durability | Class 3 Moderately Durable | Class 2 Durable |
| Stability | Excellent | Excellent |
| Fire (E84) | Class C indicative | Class B indicative |
| Radial Shrink | 4.8WD % | 4.2WD % |
| Tangential Shrink | 7.6WD % | 6.9WD % |
| T/R Ratio | 1.58 | 1.64 |
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 | 🥇 Sweet Chestnut | ★★★★☆ |
| Exterior cladding | 🥇 Sweet Chestnut | ★★★★☆ |
| Flooring / wear surfaces | 🥇 Sweet Chestnut | ★★★☆☆ |
| Furniture / interior joinery | 🥇 Douglas Fir | ★★★★☆ |
| Structural / load-bearing | 🥇 Douglas Fir | ★★★☆☆ |
Advantages & limitations
Douglas Fir
Advantages
- Very low movement in service
- Easy to machine, glue and fasten
- Lightweight — easy handling and installation
Limitations
- Soft surface — dents under point loads
Sweet Chestnut
Advantages
- Rated for exterior exposure (EN 350 Class 2)
- Very low movement in service
Limitations
- Soft surface — dents under point loads
Recommendation
Choose Douglas Fir if…
- You want the stronger all-round engineering profile
Choose Sweet Chestnut if…
- Outdoor durability is the priority
- Its profile matches the application better than a single overall score
Frequently asked questions
Which is more durable, Douglas Fir or Sweet Chestnut?
Sweet Chestnut — it carries the better EN 350 rating (Class 2 vs Class 3). Lower class numbers mean higher natural durability.
Which wood is better for outdoor use?
Sweet Chestnut — outdoor performance combines decay durability with dimensional stability, and it leads on that combination.
Is Douglas Fir harder than Sweet Chestnut?
No — Sweet Chestnut is harder (Janka 680 vs 620 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.