The best choices in timber for decking may be discovered by weighing the options that include weather conditions, the effect of the environment and presence of termites and other pests in the area. Hardwood that is conducive and resilient to the area's conditions will be the best choice in the long run.
Characteristics of some timber considered for decking
Treated Pine
Pine trees have a lifespan of hundreds of years. However, Pine trees have many disadvantages when it comes to construction as it decays fast and it may not last very long if attacked by pests and weather conditions. Natural pine may be used for paneling or for making furniture, but it is not recommended for decking etc. One variety of Pine trees, the Huon Pine is actually decay resistant. However, it takes a long time to mature and as a result, it can get very expensive. One way to lengthen the life of Pine wood is to use wood preservation techniques and appropriate construction regulations.
Silvertop Ash
Silvertop Ash or Coastal Ash trees grow in Australian table land and in the coastal areas. The color of the wood may be a pink or pale brown which can look quite elegant. Although it has a medium texture and the sap wood is not distinguishable, it is easy to bend and generally used for manufacturing handles and other simple things. This wood dried very slowly and is used for general construction. Due to the low resistance to termite attacks and low natural durability with ground contact, it is not a very good choice for decking.
Spotted Gum
The wood of the Spotted gum tree is dark brown or chocolate in color. The grain varies with individual species and the wavy grains are very attractive. It is easy to work with Spotted Gum wood. It has wonderful resistance to termites and the hardness is rated average whereas durability is rated very high. It is excellent for decking work and its availability locally in Australia makes it cost effective.
Iron Bark
The color of Iron Bark timber varies from pale brown to dark red.The texture is moderately course, even and grains are interlocked. The wood is heavy and difficult to work with and it is difficult to plane and hard to nail. Drying needs gentle care and the process is often slow. The Iron Bark timber has good resistance to attacks from termites. Natural durability of this wood is rated as 'very good'. It is often used for heavy engineering work, ship building, flooring and decking.
River Red
River red gum is attractive with reddish brown appearance. Texture is even and fine. Grains produce an attractive ripple. Bending is difficult but resistance to termites is good. Natural durability is Class 1 and hardness is average. Overall it is a good wood for decking.
Jarrah
Jarrah is available in rich red and deep brown in color. Grains are straight whereas texture is little coarse but this could be even too. Drying is easy and bending is possible. Density of wood is high but easy to work with sharp tools. Durability and resistance to termites makes it a good choice to be used in deck.
Silvertop Stringybark
The color of the Silvertop Stringybark is an attractive pale brown with a pinkish tinge. It is straight grained with even structure although it is not much resistant to termites. Durability and hardness is average but it can be used for flooring.
All the woods described above are different variations of Eucalyptus and are abundantly available in Australia. These woods are reasonably good for making decks which are naturally durable and in some cases, the durability may be increased by treatment