JANKA Hardness (*) | Life expectancy (**) | Product types (***) | Comments | |
---|---|---|---|---|
Thermaly modified wood
| Ash: 1,400 lb 37 lbs/ft3 5-7% moisture content | Ash 25-30 yrs SYP 20 yrs Spruce 25 yrs Ash 1 - Ground contact SYP 2 - No ground contact Sprouce 1 - Ground contact | Decking Lumber 16" ac. joist spacing for decks SS screws or hidden clips. No predrilling | Moisture content is about half that of the untreated species. Wood grain is pronunced and TM ash is dark brown. Surface can be treated with natural oil products to delay graying and weathering. Thermaory`s Joint End Matched (JEM) joints allow docking to end between joints, saving time and cuts. Ash and SYP are grown in U.S. but treated in Estonia. FSC certified is avaliable special order. |
Acetylated
| Radiata: 930 lbs/ft3 3-5% moisture content | Radiata 25yrs in ground contact, 50yrs above ground Radiata 1 - Ground contact SYP 2 - No ground contact | Decking, Lumber, Laminated Lumber, Use SS screws, Predrilling recommended | Radiata pine is fast growing compared to ash, but grown in New Zealand and treated in the Netherlands. Swelling and shrinkage is reduced by 75% or more. Outperiforms CCA-treated lumber in in-ground stake testing. Accoya is C2C Gold Certified. |
Polymerized / Kebonized wood
| Radiata: 1,619 lb 37-42 lbs/ft3 SYP: 1,708 lb 42-53 lbs/ft3 | No info on life expectancy Radiata 1 - Ground contanct Scots pine - 1, 2 - No ground contact SYP 2 - No ground contact | Decking Lumber, Use SS screws avoid galvanized 16" ac. joints spacing for Radiata decking 24" ac. for SYP and Scots pine decking Predrilling requiered | Scots pine and Radiata pine decking are avalaiable FSC certified. Scots pine and grain cuts should be treated with a wood preservative. Radiata pine is grown in New Zealand and treated in Norway. Close to 50% more weight is added with treatment. |
Black Locust
| 1,700 lb 48 lbs/ft3 11% moisture content | 50+ yrs 1 - Ground contact | Decking, Lumber, Custom sizes and shapes | Only heartwood is decay resistant, not sapwood. |
IPE
| 3,510 lb 69 lbs/ft3 12-18% moisture content | 40+ yrs 1 - Ground contact | Decking, Lumber Screws and nails must be predrilled. Use SS screws, avoid galvanized. | Heartwood is more decay resistant. FSC certified adds significant cost. Challenging to build with. Hard and dense with high cutting resistance during sawing. Grain can tear out durring sanding. Oily wood does not take finishes or glues easily. |
Cumaru
| 3,330 lb 68 lbs/ft3 12-18% moisture content | 40+ yrs 1 - Ground contact | Decking, Lumber Screws and nails must be predrilled. Use SS screws, avoid galvanized. | Heartwood is more decay resistant. FSC certified adds significant cost. Challenging to build with. Hard and dense with high cutting resistance during sawing. Grain can tear out durring sanding. Oily wood does not take finishes or glues easily. |
Redwood
| 450 lb 26 lbs/ft3 10-14% moisture content | 10 - 15 yrs Heartwood is 2 - 3 | Decking, Lumber | Very soft. Not durable in high traffic settings. Only heartwood is decay resistant. Decay resistance varies. |
Western red cedar
| 360 lb 23 lbs/ft3 10-14% moisture content | 10 - 15 yrs Heartwood is 2 | Decking, Lumber | Very soft. Not durable in high traffic settings. |
( * ) JANKA Hardness - (PUNDS-FORCE - LB) / Density (AVERAGE DRY WEIGHT - LBS/FT3
( ** ) LIFE expectancy in use and durability class (EUROPEAN MEASURE OF DECAY RESISTANCE)
( *** ) Product types and constructability notes
- 1 = very resistant
- 2 = resistant
- 3 = moderatley resistant
Common Name(s):
Black Locust, Robinia, False Acacia
Scientific Name:
Robinia pseudoacacia
Distribution:
Central-eastern United States (also widely naturalized in many temperate areas worldwide)
Tree Size:
65-100 ft (20-30 m) tall, 2-3 ft (.6-1 m) trunk diameter
Average Dried Weight:
48 lbs/ft3 (770 kg/m3)
Specific Gravity (Basic, 12% MC):
.66, .77
Janka Hardness:
1,700 lbf (7,560 N)
Modulus of Rupture:
19,400 lbf/in2 (133.8 MPa)
Elastic Modulus:
2,050,000 lbf/in2 (14.14 GPa)
Crushing Strength:
10,200 lbf/in2 (70.3 MPa)
Shrinkage:
Radial:4.6%
Tangential: 7.2%
Volumetric: 10.2%
T/R Ratio: 1.6
Color/Appearance:
Color can range from a pale greenish-yellow to a darker brown. Tends to darken to a russet brown with age. Can be confused with Osage Orange and Honey Locust in some instances.
Grain/Texture:
Grain is usually straight, with a medium texture.
Endgrain:
Ring-porous; large earlywood pores 2-3 pores wide, small latewood pores in clusters and tangential bands; tyloses extremely abundant; growth rings distinct; narrow to medium rays barely visible without lens, spacing normal; parenchyma vasicentric, lozenge, and confluent.
Rot Resistance:
Rated as very durable in regards to decay resistance, with good weathering characteristics. Frequently used as fence posts for its outdoor longevity.
Workability:
Overall working characteristics for Black Locust are mixed: although the grain is usually straight, its high density and hardness can make it difficult to machine. Black Locust also has a moderate blunting effect on cutting edges. Responds very well to both lathe turning and steam bending; glues and finishes well.
Odor:
No characteristic odor.
Allergies/Toxicity:
Although severe reactions are quite uncommon, Black Locust has been reported to cause eye and skin irritation. Another (uncommon) side effect reported is nausea. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.
Pricing/Availability:
Black Locust prices can vary depending on location, but prices should be moderate within its natural range. Those living in the eastern United States can expect prices to be comparable to White Oak. In other areas where the lumber has been imported, the prices can be much higher.
Sustainability:
This wood species is not listed in the CITES Appendices, and is reported by the IUCN as being a species of least concern.
FSC®:
We are a certified source of Black Locust worldwide. Please contact us for FSC® certified products.