What’s in a Deck

Before we touch on the decking species that are available, it makes sense to briefly cover exactly what is required to build a deck for the uninitiated. Most timber decks are supported by strategically placed posts which are bolted to post shoes or stirrups above the ground. 

This ensures that the posts won’t decay and destabilise the deck. Attached to the top of the posts are bearers, which run parallel to each other along the deck. The bearers are usually the largest timbers in the deck and serve to stabilise and underpin the structure. Joists then run across the bearers and sit on top of them, normally at right angles to the bearers. Finally the decking boards are fixed to the top of the joists and run across the joists and in the same direction as the bearers. 

The calculation of the sizes of bearers and joists is a complicated process involving sophisticated engineering and many variables. For an overview please visit this decking blog post.

This simple decking structure can be amended in many ways to create elaborate decks that are suspended from the side of a home, have multiple levels or unusual shapes.

Softwoods Decks

The substructure of Softwoods decks is usually Treated Pine. We find that H3 Kiln Dried treated pine provides little to no movement, is resistant of rot and insect attack, and is also the most economical option. Our posts sit on hot dipped galvanised steel posts shoes (or stirrups) and we use galvanised bolts to further ensure no rusting will affect your structure. Bearers are bolted to posts and joists are secured to bearers using trip-l-grip or uni-tie brackets and galvanised nails. All of these measures have been developed over the years to ensure that a Softwoods deck is built to last.

Types of Decking

The primary variable aside from size and shape of decks is the type of decking board that you use. Decking comes in many different species, offering variable strength, size and flexibility, as well as colour, grain and density. With these variables come different prices and performance. Softwoods provide a large range of decking options to ensure that we can provide you with what you want in a deck at a price that suits you.
Below is a brief description of the varieties of decking we specialise in, as well as some information about each. Each variety has ratings for Density, Toughness, Durability and Colour taken from a paper by the National Association of Forest Industries. The ratings are explained below:

• Density Rating for seasoned timber is a measure of mass in kilograms per cubic metre. Density rating is a great indicator of the strength of the timber and serves as a good comparison between species. The higher the mass, the more dense the timber is.
  Toughness Rating is a measure of impact resistance or strength of the timber, measured in Newton metres but simplified to Low(up to 15) Medium (15 to 25) and High (25 and over)
• Durability Class consists of four classes based on tests carried out on untreated heartwood. A score of 1 indicates high durability with the expectation of resistance to decay for over 40 years. Class 2 offers high durability with an expectancy of 15 to 40 years decay resistance. Class 3 is moderate durability with 7 to 15 years resistance and Class 4 is low durability with 1 to 7 years expected resistance. Please note also that the timbers tested are untreated and undried, as well as unpainted or stained. Once treated and stained timber can be expected to last for much longer than anticipated here, but these scores show well the variability and qualites of the differing species.
• Colour is coded as below and gives an indication of the unstained natural colour of the timber.
• W- White, Yellow, Pale Straw, Light Brown
• P- Pink to Pink Brown
• R- Light to Dark Red
• B- Brown, Chocolate, Mottled or Streaky

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