composite decking product review

composite decking brands in review

The Colorado fire that swept through and destroyed nearly 1100 houses in the 2021-22 US winter was an ominous warning.  The mandatory fire resistance product ratings in the Australian construction market offers superior construction standards for the US construction industry.At Development Approval stage, one of the five Bushfire Attack Level (BAL) needs to be specified for the building design.  The choice of composite decking effects the structure’s fire resistance in the building approval process.  Perhaps US regulators could mirror the BAL rating system with a Forest Attack Level (FAL) rating system in the US? Internationally, some composite decking choices are:

• Ekodeck (not available in US)
• Millboard
• Modwood 
• Timber Tech
• Trex

characteristics and comparisons

The major challenge for builders is how composite decking performs in summer weather conditions compared to a hardwood timber deck.  Composite decking manufacturers recommend 3/8” expansion gaps and a grid pattern/format due to the excessive expansion in direct sunlight.  Timber products don’t have the same expansion rates but the composite decking advantage is higher sustainability and lack of maintenance.  Composite decking comparisons are complex but can be assessed on four attributes:

• fire resistance rating
• cost
• color range
• proprietary fixings and format

Ekodeck

The Ekologix boards have two format sizes (in four colors) of 23x88mmx5.4m and 23x137mmx5.4m at almost double lineal meter cost.  Ekologix composite decking uses HDPE plastic throughout the entire board’s depth which means that the board maintains a more natural appearance and can be sanded.  The elimination of the cap-stock or veneer coating means that the board performs better from a sustainability design perspective but is more susceptible to staining.  Ekodeck’s competitors have eliminated the staining propensity by using a PVC composite top veneer coating.  The PVC top veneer reduces a boards capacity to cope with heavy knocks and punctures as the composite decking color and texture isn’t throughout the.  Although cost competitive, Ekodeck composite decking does not achieve a BAL rating.

Millboard

Millboard is sold by Outlive is 100% more costly than Outlive standard composite board Modwood.  The Australian made product is not fire-rated (or BAL rated) so the reason for the increased pricing structure could be the shear volume of required raw material as the format sizes are either approximately 3/8”x7” 2/8”x12’ lengths or 3/8”x8”x12’ lengths.  The nine color range also has availability in weathered textures.  This product can only be fixed with the proprietary stainless steel star head screw.  The supply cost of the boards and the associated cost of the fixings certainly will almost invariably result in this product only be specified in up-market individual houses.

Modwood

Modwood is also only available as grooved decking which is supplied at a more competitive price than Millboard.  The most important feature of Modwood is that achieves a BAL 40 rating when using the ungrooved profile with two format sizes of Modwood are 1”x3” 4/8”x18’ and 1”x5” 3/8”x18’.  Clients should remember the labor cost for fixing the boards is increased with the narrower widths when assessing the apparent supply cost savings.  Modwood is available in four color shades with smooth or brushed finish.  The boards are glue fixed into a galvanized, powder-coated galvanized or stainless steel proprietary fixing system (called ‘Klevaklip’).

Timber Tech

Timber Tech supplies six ranges of product and nineteen colors of varying brushed or smooth finishes internationally – the square edged XLM Plank range is the only range with a BAL 29 rating.  The format size is 5”2/8”x1”mm for both the square edge and grooved boards with sectional profiles similar to Trex.  The reduced BAL rating means that this product is unsuitable for specification in bush fire prone areas or BAL 40.

Trex

Trex Decking offer 20 colors to the US construction market in square edged and grooved composite decking.  The diversity of colors and quality of finish of the boards are major advantages for specifying this for your next project but lacks high fire-resistance with BAL 29 rating.  Interestingly, some Australian hardwoods also achieve a BAL 29 rating.  The grooved boards use the proprietary fasteners that create 2/8” gaps – AS 3959-2009 stipulates resistance against ember attack requires a 1/8” gap.  Trex arguably  leads composite decking technology accumulating thirty years of manufacturing composite decking.  The format size is either 1”x5”4/8”x16’ or 1”x5”4/8”x19’5/8” so the composite decking are expeditiously installed with reduced labor than the wider and longer composite decking lengths.