Janka hardness for imported wood species The Janka Hardness of Imported Wood species measures the force required to push a steel ball with a diameter of 11.28 millimeters (0.444 inches) inside the wood to a depth of half the ball's diameter (the diameter was chosen to produce a circle with an area of 100 square millimeters). In the Janka's original test, the results were expressed in units of pressure, but when the ASTM standardized the test (tentative issue in 1922, standard first formally adopted in 1927), it called for results in units of force.{/tabs}

Janka Hardness of Imported wood species is the industry standard for gauging the ability of various wood species to tolerate denting and normal wear, as well as being a good indication of the effort required to either nail or saw the particular wood.

In the United States, the measurement is in pounds-force(lbf) . The hardness of wood usually varies with the direction of the grain remember that is usually 3 popular wood cuts plain sawn, quarter sawn and rift sawn . If the Janka Hardness test is done on the surface of a wood plank, with the force exerted perpendicular to the grain, the test is said to be of "side hardness." Side hardnesses of a block of wood measured in the direction of the tree's center (radially) and on a tangent to the tree's rings (tangentially) are typically very similar. End testing is also sometimes done (that is, testing the cut surface of a stump would be a test of end hardness). The most common use of Janka hardness ratings is to determine whether a species is suitable for use as wood flooring or contruction frame. Moisture Content is always a variant on any janka hardness test or table this mean that, side hardness increases with decreasing moisture content. In short in the Janka hardness The higher the number, the harder the wood.




Imported wood species types

Bambo or Scientific Name: Phyllostachys vivax Properties: Bamboo is a renewable resource due to its short growth time requirement. It only takes about four years from planting to harvest time to prepare it for flooring applications. This flooring also has the added benefit of being highly resistant to moisture absorbtion. Therefore if humidity is an issue, bamboo flooring offers a material which will remain true in shape. Janka Hardness: 1180

Brazilian Cherry or Scientific Name: Hymenaea courbaril Properties: In addition to its warm reddish tint, this moderately lustrous wood is notable for its hardness and durability jatoba is extremely dense wood and very strong. Janka Hardness: 2350

Bubinga or Scientific Name: Guibourtia spp Properties: Bubinga wood is durable and has a natural resistance to termites. This species requires time and care to dry properly. If adequate time is not provided, warping can occur. The wood is not reported to have any distinctive odor. Janka Hardness: 2690

Cork or Scientific Name: Quercus suber) Properties: Cork species do not usually have a high resistance to decay, but they do have a propensity to absorb preservatives rather well. The wood commonly has no odor. Most Cork are not difficult or time consuming to dry properly. Janka Hardness: 380

Curmaru or Scientific Name: Un/know Properties: Works well, but is very hard use carbide blades and bits. Janka Hardness: 3540

Cypress or Scientific Name: Callitris glauca Properties: This species grows in a semi-arid area of Australia, which bestows on it the unique property of being the only commercial softwood that is actually harder than red oak — making it superior for both residential and commercial use. Because of its relative hardness and excellent durability, Australian cypress wood flooring has very good dimensional stability; however, in actual installations, significant movement can sometimes be seen. Janka Hardness: 1375

Gum spotted or Scientific Name: Eucalyptus maculata Properties: Spotted gum has a high natural resistance to decay. The wood remains smooth under friction and is reported to a slight citrus-like odor. Spotted gum dries fairly easily. Janka Hardness: 2473

Gum Sidney or Scientific Name: Eucalyptus saligna Properties: Sydney blue gum wood is very hard and tough, and moderately durable. This species can take some time to dry properly to prevent checking and warping. Janka Hardness: 2023

Iroko or Scientific Name: Chlorophora spp Properties: Iroko is a very heavy, strong, durable wood. It is hard and stiff, with excellent shock-resistance. Janka Hardness: 1260

Jarrah or Scientific Name: Eucalyptus marginata Properties: Jarrah is very hard and durable, with a bending strength much greater than that of Mahogany. It has moderate resistance to decay when not chemically treated. The wood remains smooth under friction and is reported to be odorless. Amendoim is a dimensionally stable wood flooring species. Janka Hardness: 1910

Mahogany (santos) or Scientific Name: Myroxylon balsamum Properties: Mahogany is known for its strength and beauty, and it has outstanding durability. Given its hardness and color-fastness, santos mahogany is a superior choice to genuine Honduran mahogany (Swietenia macrophylla), which it closely resembles in color. In fact, although genuine mahogany is traditionally chosen for fine furniture and millwork, it is seldom used in wood flooring because it lacks sufficient hardness to withstand constant foot traffic. Janka Hardness: 2200

Maple (Brazilian) or Scientific Name: Acer saccharum Properties: Like black maple (B. nigrum), maple is classified as a hardwood (other species of maple are considered soft). And like teak and white oak, it has a high crushing strength. It is stiff, strong, dense, and extremely tough, with excellent shock resistance. It is notably resistant to abrasive wear; and for this reason, it is the hardwood flooring of choice for such high-traffic/hard-use locations as bowling alleys, basketball courts, and other sports facilities. Janka Hardness: 1500

Merbau or Scientific Name: Intsia biuga / Intsia palembanica spp Properties: Merbau is almost as stable as teak. And although comparable to hickory in strength, merbau has a much lower density. It has excellent dimensional stability and is highly resistant to termites. Janka Hardness: 1925

Oak (Tasmanian) or Scientific Name: Eucalyptus delegatensis Properties: Tasmanian oak does not have a natural resistance to decay, and lacks any noticable odor. Tasmanian oak requires some care to dry properly as checking can occur. Janka Hardness: 1350

Padauk or Scientific Name: Pterocarpus soyauxii Properties: Harder and more stable than northern red oak, padauk is heavy and strong and has an average to high durability. It has excellent weathering qualities and is highly resistant to decay. Janka Hardness: 1725

Purpleheart or Scientific Name: Peltogyne spp. Properties: Purpleheart is a very hard, dense, strong wood, with excellent dimensional stability. It is very resistant to dry-wood termites. Janka Hardness: 2890

Sapele or Scientific Name: Entandrophragma cylindricum Properties: Sapele is quite durable and seasons rapidly, but with a marked tendency to warp, so careful stacking is required. Janka Hardness: 1510

Teak (Brazilian) or Scientific Name: Tectona grandis Properties: Teak has a high resistance to decay and termite attack. In fact the oil secreted by the wood is reported to be a natural insect repellant. The wood remains smooth under friction and is reported to have the odor of leather when freshly cut. Chestnut is diffuclt and time consuming to dry properly. Janka Hardness: 3540

Walnut brazilian Ipe or Scientific Name: Juglans nigra Properties: the wood is heavy, hard, and stiff and has excellent dimensional stability. It is moderatly dense, but very strong, with good shock resistance. Janka Hardness: 3680

Wenge or Scientific Name: Millettia laurentii Properties: Like black maple (B. nigrum), maple is classified as a hardwood (other species of maple are considered soft). And like teak and white oak, it has a high crushing strength. It is stiff, strong, dense, and extremely tough, with excellent shock resistance. It is notably resistant to abrasive wear; and for this reason, it is the hardwood flooring of choice for such high-traffic/hard-use locations as bowling alleys, basketball courts, and other sports facilities. Janka Hardness: 1500