Chlorophora excelsa
Iroko
Also known as: Odum, Kambala
Timber GrainAbout this Timber
General Description
Iroko is golden orange to brown, lighter vessel lines are conspicuous on flat sawn surfaces. Colour darkens with age. The grain is interlocked and sometimes irregular and the texture rather coarse but even.
Working Properties
How This Timber Works
The timber works satisfactorily with hand and machine tools but with a moderate to severe blunting effect. The wood nails and screws well, glues satisfactorily and when the grain is filled an excellent finish can be obtained.
Mechanical Properties
This medium density wood has a moderate steam bending classification, with medium crushing strength, very low stiffness and resistance to shock loads.
Technical Data
Technical Specifications
*Air Dry Density (kg/m³) is an average indication only and actual values may vary. Refer to strength, shrinkage and durability classification tables for full details.
Reference Tables
Timber Classification Tables
Standard NZ classification tables for strength groupings, shrinkage and durability. This species is highlighted in each table.
| Strength Group | Modulus of Rupture | Modulus of Elasticity | Max Crushing Strength |
|---|---|---|---|
| S1 | 103 | 16300 | 52 |
| S2 | 76 | 14200 | 43 |
| S3 | 73 | 12400 | 36 |
| S4 | 62 | 10700 | 31 |
| S5 | 52 | 9100 | 26 |
| S6 | 43 | 7900 | 22 |
| S7 | 36 | 6900 | 18 |
| Strength Group | Modulus of Rupture | Modulus of Elasticity | Max Crushing Strength |
|---|---|---|---|
| SD1 | 150 | 21500 | 80 |
| SD2 | 130 | 18500 | 70 |
| SD3 | 110 | 16000 | 61 |
| SD4 | 94 | 14000 | 54 |
| SD5 | 78 | 12500 | 47 |
| SD6 | 65 | 10500 | 41 |
| SD7 | 55 | 9100 | 36 |
| SD8 | 45 | 7900 | 30 |
| Description of Shrinkage | Tangential | Radial |
|---|---|---|
| Very Low | 0 – 3.5 | 0 – 2 |
| Low | 3.5 – 5.0 | 2 – 3 |
| Medium | 5.0 – 6.5 | 3 – 4 |
| High | 6.5 – 8.0 | 4 – 5 |
| Very High | > 8.0 | > 5 |
| Grade of Durability | Fully Protected | Above Ground, Exposed | In-Ground, Exposed |
|---|---|---|---|
| Very Durable | > 50 | > 40 | > 25 |
| Durable | > 50 | 15 – 40 | 15 – 25 |
| Moderately Durable | > 50 | 7 – 15 | 5 – 15 |
| Non-Durable | > 50 | 0 – 7 | 0 – 5 |
Applications
Main Uses
Stock & Sizes
Availability
Kiln-dried sawn 25mm, 40mm, 50mm and 75mm thicknesses in mixed widths.
Quality Standard
