Random Deck

Download the Random deck tech data sheet (pdf format) HERE

1.0 Product

Radially sawn Random BE Decking is a radical alternative to conventional decking systems. Radially sawn boards are produced by cutting logs into wedges and then resawing these wedges to produce back sawn decking boards. Back sawn boards can be identified by the alignment of growth rings, which are basically parallel to the broad face of the board. Random BE Decking is unseasoned, fine sawn and generally supplied in two alternating width boards.


2.0 Specifications

2.1 Species

Bevelled edge decking boards are sawn from regrowth native hardwoods such as Silvertop Ash (ie. Class 2 durability). Other species (including Class 1 durability) 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

Random Deck in cross section

2.4 Profile

Random Decking is typically supplied as a series of 25mm thick boards that alternate in width and feature 22.5 degree bevelled sides (see Figure 1 above). The widths of these boards are typically 100mm but other width combinations may be available from Radial Timber Sales as a special request (NOTE: narrow face of the wide board is actually around 80mm wide). Random Decking boards feature a fine sawn finish and are supplied unseasoned (ie. will shrink naturally).

2.5 Lengths and Availability

All Random Decking orders require a min. of 2 – 3 weeks lead time from the confirmation of order. Boards are generally supplied in random lengths of between 1.5 and 5.4m (av. lengths approx. 4.0m). Set length boards may be available on request from Radial Timber Sales (a surcharge will be applicable to all set length orders). Random Decking is ordered by the square metre.


3.0 Fixing & Applications

3.1 Fixing Recommendations:

Setting up: Random BE Decking is typically installed by alternating wide and narrow boards. The effects of cupping will be minimised by installing the deck with the wide face of the narrow board down and the wide face of the wide board up (see Figure 1). To reduce splintering, it is recommended that the sharp, exposed edges of the narrow boards be planed on site prior to fixing. Joists can be spaced at 500 to 600mm centres.

Installation: Decking boards should be fixed with minimal or no gap to allow for natural shrinkage (approx. shrinkage of 7% or 5-6mm per 100mm of board is normal). It is not uncommon for boards to be slightly drier on the ends, thus resulting in minor variations in width and line. When butt jointing the decking, it may be advisable to end dock the boards or at least fix to the centre-line of the boards and ignore any minor variations in width (ie. most variation will diminish as the boards fully season).

Fixings: Boards can be gun or hand nailed with 65mm twisted or ring shank nails or fixed with 50mm batten screws but care should be taken close to the ends to avoid splitting (it may be necessary to pre drill if hand nailing. All fasteners should be galvanised or stainless steel. A fixing rate of two fasteners per board per joist is recommended.

Seasoning & Storage: Some surface checking may occur during seasoning but these non structural cracks will close again as moisture content in the boards equalise (NOTE: unprotected west facing decks may be subject to extreme temperature changes and therefore, timber is more likely to check or move). It is normal for all hardwoods to leach red/brown extractives during heavy rain periods. Extractives tend to be less prominent in lighter species but it may be advisable to protect walls/paving until the extractives have finished leaching (can vary but leaching will generally continue for up to 6 months). Packs should be kept wrapped, weighted and off the ground in a level position before fixing to prevent uneven drying or distortion.

3.2 Suggested Applications

Random Decking has been used as a rustic alternative to traditional decking products on: houses, schools, visitor centres, ramps, boardwalks and bridges. For images of Random Deck visit the deck product galleries.


4.0 Finishing

Being an unseasoned product boards will mark and stain easily especially when they come into contact with rain or metal. It’s best to clean all boards down with a 5% solution of oxalic acid after installation to obtain a clear timber surface (we can supply oxalic acid).

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. Radial 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. For more detailed information, please refer to Radial Timber “Finishing Recommendations” at: www.radialtimbers.com.au or call Radial Timber on 03 9768 2100.