Reliability, high quality, efficiency, Germany – the words somehow seem synonymous. There’s usually little doubt that when a long-standing German manufacturer brings a product to market, it has been developed, tested and proven to work – very efficiently. Werzalit’s holds up its decking material, “terraza”, as a perfect example.

Werzalit AG started in 1923 as a glue company and developed into a manufacturer of timber-based components, found across a wide range of industries, including automotive, construction, furniture and sports equipment.

Frieder Werz took the company on from his father Jakob in 1946 and was the inspiration that grew the business to a corporation including sites in Germany, US and Romania, with over 600 patents in 43 countries and various manufacturing licences, before selling it to ISO Holdings in 1987.

In 2004 Jochen Werz, Frieder’s son, regained control of the business and is now firmly at the helm of the Oberstenfeld company, building new product lines and innovations to continue Werzalit’s growth.

“Our products are durable and designed to outlast the competition. With over 50 years’ experience in external applications for composite timber products, we have an excellent core knowledge,” said Mr Werz. “As our fully-finished exterior cladding, balcony components and external table tops developed, we’ve sometimes learned the hard way, but we have taken a different avenue from other manufacturers to ensure that terraza decking is an excellent product, because of that extensive knowledge.”

Virgin fibre

There is already a range of composite decking materials on the market, with the US an inevitable home for many volume producers, but Werzalit has redefined the position for the ultimate composite decking product. “We use virgin timber mixed with virgin polymers and the most expensive ultra violet inhibitors, in a hollow chamber extrusion method,” said Mr Werz. “Initially the numbers looked well above the market price, but we had to ensure reliability and took a lot of cautious measures, as we couldn’t afford a failure. We have accepted that terraza will be at the top of the price range, but with its patented Klicktechnik system it will give excellent overall costs.”

The latter gives the decking fitter a choice of narrow or wide gap appearance, while actually creating one single floating deck layer, with no gaps. The first board is face fixed and then subsequent boards are clicked together before being fixed through the edge, giving a totally concealed fixing, leaving clean, undamaged profile faces, which all assist the product to remain durable. The appearance is initially surprising, because there are almost no fixings in sight. It is also easy to join, reducing installation times.

While many elements of the production are closely guarded secrets, Martin Lindenberger, export manager for building products, explained the processes that ensure terraza decking meets the stringent specifications of Werzalit, “Right from the start we’re using the very best ingredients,” he said. “All of our cladding and table tops are also produced at this site from an equal mix of spruce and beech, with a small amount of poplar.”

By using virgin wood – all PEFC-certified – the company has complete control over the wood chips, which are dried to a very low moisture content.

Strength and durability

“The chips are then mixed to a specific ratio with pre-coloured, granulated virgin polypropylene, creating the perfect balance of strength and durability,” said Mr Werz. “We do not use recycled material, but some additives before the mixture is heated and extruded through a stainless steel mould. The extrusion is then cooled and calibrated to give a precise section, finally having its product marking and wire brushing of the surfaces, to create a roughened non-slip surface.”

The product, which is available in Sabbia, a light brown; Topino, a greenish hue; and Terracotta, is then cross-cut to 3, 4 and 6m lengths and packaged, ready for shipment. End caps, extruded 38×71.5mm substructure battens and solid 12x40mm strips (for low or high profile bearers) complete the package.

Testing carried out during development included the V20 test, where samples were immersed in water for 24 hours. The results showed swelling at a low 2%. “Terraza gives the ideal balance, leaving the polypropylene to seal the wood chips while giving a high timber content,” said sales director Dr Klaus Hoffmann.

Inevitably comparisons will be made to softwood and hardwood timber decking and, while purists will always argue for natural timber, Werzalit says there is a place for a composite product with its own features and benefits. According to Mr Lindenberger, terraza has excellent non-slip properties, and gives time and cost savings by fixing at 600mm centres – wider than most decking materials – and using the secret fixing detail and click jointing system which allows fitting at 8-10m2 an hour.

Design options

Two face patterns and a narrow or close click fitting system, he added, give plenty of design and appearance options, and, at 2.3kg per metre run, it is light compared to other composite or timber decking products. Terraza can withstand a temperature range of -50 to +70OC with no width shrinkage, it is knot-free and does not suffer resin exudation or fungal attack. It is also resistant to weather, seawater, damp, and chlorine.

It’s closed system means dirt and rubbish cannot fall between boards – drainage occurs through a pre-designed fall. And, at the end of its useful life, the company says, like timber, it can be recycled.

Terraza was launched on the German market in 2005 and as Werzalit has widened its sales network, the company’s initial sales projections have been outstripped. “To date, 2006 sales are over double what we expected and we’re increasing production all the time,” said Dr Hoffmann. “We expect to double capacity again in 2007.”

UK distribution is simplified by the large existing sales of Werzalit’s table top and cladding products, allowing a rapid turnaround of orders for delivery into the UK in pallet quantities.

The Werzalit team is guarded on capacity and growth, but there is no doubt that the Oberstenfeld factory has the ability to increase levels dramatically, as Mr Werz explained: “The UK market is very interesting for us. With a large coastline and variety of climates, we know that terraza is ideal for many situations, particularly when its total life cost, including fitting, is calculated. For domestic and public facility requirements it will make an interesting option for the UK and we’re keen to develop it with distributors.”