Pencil Round Deck

Download the Pencil Round Deck tech data sheet (pdf format) HERE

1.0 Product

Pencil Round decking is the most common profile of decking available.It has a smooth finish and is always supplied as a seasoned (dry) product.


2.0 Specifications

2.1 Species

Pencil Round boards are typically supplied sawn from naturally durable regrowth hardwoods such as Ironbark and Spotted Gum (Durability Class 1). Other species (including Class 1 & 2) may also be available on request. Both Class 1 & 2 timbers are deemed suitable for use as decking in Australian Standard AS 080-1693.

2.2 Grade

All timber is supplied as standard and better and is not select. Small tight knots, gum veins, splits, ambrosia (pin hole) and other marks are acceptable features that sometimes occur in boards.

Timber is graded in accordance with AS27462 – 1994 Australian Standard Part 2 Grade description.

2.3 Sketch / Sections

Pencil Round Deck in cross section

2.4 Profile

Pencil Round boards are 19mm or 32mm thick and typically supplied in a smooth dressed and seasoned (dry) width of 86mm or 135mm.

2.5 Lengths and Availability

This decking is generally kept in stock. Boards are supplied in random lengths of between 1.5 and 5.4m but some shorter lengths may also be included. Set lengths are unavailable as per National Forestry Standards.

Engineered Set Lengths (ESL)
Engineered Set Lengths are finger joined boards produced to specified lengths, and are held in stock lengths of 5.4m when shorts are available from the mill. Special length ESL orders will only be available as supply allows and availability.


3.0 Fixing & Applications

3.1 Fixing Recommendations:

Setting up: Gaps should be left between boards to allow for swelling during wet weather. The amount of swelling (or shrinkage) will vary depending on the width of the board, the species of timber and local climatic conditions. Joists should be spaced at max. 450mm centres.

Installation: For most typical installations, the following spacing guide should be followed but also consult Outlast Timber for site specific recommendations (eg. in areas subject to high moisture such as south facing decks or in bush settings, it may be advisable to increase the spacing between boards to allow for additional swelling):

  • 86×19: 5 to 6 mm gaps between boards
  • 135×19: 6 to 8 mm gaps between boards

Fixings: Decking can be gun or hand nailed with 50mm long hot dipped galvanised or stainless steel twisted shank or œring shank nails or decking screws, but care should be taken close to ends to avoid splitting (pre-drill all holes if hand nailing). 86 & 135 boards should be fixed with 2 nails per board per joist (position nails approx. 20mm in from edge of board).

Seasoning & Storage: Some surface checking may occur if timber is exposed to the weather but these non structural cracks are typical in most Australian hardwoods. It is also normal for hardwoods to leach red/brown extractives during heavy rain periods. Extractives tend to be less prominent in lighter species but it is advisable to cover or protect walls and paving until all extractives have leached (can vary depending on rainfall but will generally continue for up to 6 months). Packs should be stored up off the ground and under cover or protected with an additional tarp to prevent swelling. If wetting does occur, allow a min. of 24 hours for timber to dry before fixing.

3.2 Suggested Applications

Ironbark and Spotted Gum is a stylish and popular decking and has been used in: houses, apartments, visitor centres, restaurants, parks, screens and fences. For images of Ironbark and Spotted Gum decking visit the Outlast Timber website.


4.0 Finishing

All exposed, externally fixed decking will tend to fade to a silver grey colour if left uncoated. The degree of greying will vary depending on the amount of exposure to sun, wind and rain. The timber used in this above ground product has natural durability and when used in conjunction with good building practices, should generally not require additional treatment against decay.

Native timbers should be offered some weather protection while acclimatising to local conditions. Outlast Timber recommends the application of an oil based sealer or decking finish on external timber (especially if unseasoned or fixed during extreme weather conditions). There are a variety of treatments, stains and coatings available and most can be applied prior to or shortly after fixing.