The best way is start is to consider the factors that are most important to you, your particular circumstances and the proposed deck location and then give a weighting to each factor to come up with the best option. Everyone's situation is slightly different, so what's best for you, may not be appropriate for someone else.



There are probably seven most relevant factors which you should take into account when deciding what lumber species is best for your situation. These are:

Type of wood (hardwood or softwood)

Natural durability

Colour of the wood

Wearability

Ease of machining and working

Environmental considerations

Cost

Hardwood or softwood

Most softwoods with the notable exception of western red cedar, some cypress species and a few species of pine and larch are not naturally durable and will decay quite rapidly if left totally exposed to the weather. Fortunately softwood species readily accept chemical preservatives so when treated, their durability can equal or exceed most of the naturally durable hardwood species.

Durability

Durability refers to a combination of properties which includes resistance of the timber to decay, termite and borer attack and also to splitting and checking when used under exposed conditions. As wood is a natural product, it's not really possible to assign a precise or absolute value to the durability of an individual species. And the actual life which can be expected of a deck in service will be dependent on many factors including degree of exposure of the deck to the elements, prevailing weather conditions, the air circulation around the decking etc. Various charts and tables are available which list the relative durability of wood species based on their actual in service so can be used to provide a useful broad comparison between species. Note should also be taken of termite resistance if this is important in your region as this will vary greatly between species.

Colour of the wood

There is a huge color variation within wood species, from pale yellow, through brown's to reds and red orange, even purple. And some species may be very consistent in colour whilst others can vary considerably from board to board or even along the length of a single board. Some species have flecks of a paler color interspersed along the grain. However unless a strict maintenance regime involving regular oiling of the wood decking is maintained, all wood species exposed to the sunlight will eventually fade over time to a soft silver grey- the speed at which this occurs will depending on the species, the prevailing weather conditions, the degree of exposure of the deck to the sun, the intensity of the sun and the frequency of application of the protective oil.

Environmental

The destruction of the great forests of the world, not only in the Amazon basis and South East Asia but also in major Western nations, should be a major concern to everyone. Several organizations, the best known of which is probably the Forest Stewardship Council (FSC), have established standards and operating procedures which forestry owners must adhere to in order that their products may carry that organization's official certification. This provides some assurance that the wood and wood products have been harvested in accordance with sustainable forestry practises and sound forest management procedures and that any finished products have been manufactured and supplied under non exploitative labor practices. Many governments have established their own standards outside of the FSC but consideration needs to be given whether such standards and operating procedures may in fact be catering to vested interests and that some reliable and certifiable mechanism actually exists to ensure procedures and practices are indeed followed as required.

Wearability

In this rather subjective term, we are looking at what happens to the surface of the wood as it ages, how it weathers as the deck becomes older. Generally this is not such an important factor unless you like to walk on your decking with bare feet. With some species, the grain tends to lift as the wood ages, causing small splinters to appear. With other species however the surface can remain virtually smooth for years.

Ease of working with tools

Some hardwood species are exceptionally hard and thus require carbide tipped saws to speed construction. Also when nailing boards, some species can be nailed directly whilst other species will tend to split if not predrilled. Even with softwoods such as cypress, pre-drilling may be necessary.

In general, softwoods will be lower in cost than hardwoods, reflecting the shorter time to maturity of the trees, extensive plantation grown forests with easy access for harvesting and lower processing costs. Some plantation grown hardwoods can approach the cost base of hardwoods but the lower recovery rate of most hardwoods still tends to keep the price above that of most softwoods.

The above presents just an overview of the main factors you should consider when choosing a lumber species for your deck. Each of the above factors can be looked at in more detail but this should enable you to make a more considered decision on the type of lumber you would like to use for your particular decking project.