Special
Producers of wooden/composite wall cladding
WALL CLADDING STILL CHARMS US ALTERNATIVES TO WOOD ARE POPULAR TOO Wooden wall cladding has been much coveted for many years, not only for its technical features, but also and especially for the natural look and warmth of wood. Wall cladding forms a nice compromise for anyone who loves wood, but strongly prefers the classic construction method due to structural considerations. It looks like a timber structure, but it isn’t. Wood from sustainably managed forests deserves recommendation and, moreover, certain composite alternatives have emerged as ecological alternatives. For professionals this means a market which is bursting open.
The renovation solution par excellence Wall cladding is a wall finish like any other which can be fitted just as well onto a new construction as onto a renovation. It offers exquisite assets for renovation from two distinct perspectives, namely a decorative perspective and a technical insulation perspective.
From a decorative perspective There are brick wall structures which were in fashion ‘in their day’, but nowadays generally command little appreciation. There are also walls which are just shabby. Take, for instance, plastered walls with bursts and cracks or with plaster loose in some places. In such cases the only renovation option is to strip the wall and replaster it. In this case wall cladding provides a solution which is comparable with renovation panelling. It ‘buries’, as it were, the damage to the existing wall under the wall cladding.
Insulation … a great opportunity Insulation requirements are becoming increasingly strict. It is easy to meet those requirements in a new building, but with renovation it isn’t always so easy. Wall cladding can be combined with insulation on the outside. Here wall cladding has the advantage of being relatively thin. This means there is still plenty of space left for various insulation materials. This opportunity is partly due to the so called ‘Building Line Decree’. This decree was accepted by the Flemish Parliament (B) on 30 April 2009, proclaimed by the Flemish Government on 8 May, and published in the Belgian Official Gazette on 3 July 2009. Prior to that decree, basically, a wall, window frame, or staircase to the front door could not go beyond the building line. And so, it was not possible to insulate a house better on the outside to make it more energy-efficient since the insulation would have gone beyond the building line. Since that decree has been passed, there has been an exception to that rule for elements such as outdoor insulation, so it is now permissible to go up to 14cm beyond the building line.
What are the options? Strictly speaking, consumers have four groups of options for wall cladding: wood, modified wood, wood composite, and synthetics.
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Wooden wall cladding Western red cedar is certainly still one of the most popular and most frequently used types of wood. However, just as bangkirai has faced stiffer competition in recent decades from dozens of (at least) equivalent types of wood for fitting terraces, so, too, cedar wood has seen its monopoly in wall cladding disappear. Strictly speaking, we can say that wood sorts in durability classes 1 to 3 are suitable for wall cladding without the need for additional protection.
Modified wood For outdoor use with no contact with the ground, preserved larch wood and oregon are suitable for wall cladding or even less durable wood sorts such as fir and pine, provided that they undergo some form of preservation (e.g. chemical modification or thermal treatment). Nowadays, Accoya®hout (wood) is very popular as a result of acetylation. Its assets include greater dimensional stability, a harder surface, and no decline in other mechanical properties as a result of the treatment. Since 2007, there has been a commercial product on the market under the name ‘Accoya®hout’. This is made at Accsys Technologies at Arnhem in the Netherlands.
Wood composite Wood composite consists of wood fibres, high-density polyethylene, UV stabilisers, dyes, and various additives to optimise the mechanical qualities. Usually, this involves recycled wood fibres, surplus wood, and recycled polyethylene. Wood composite is in many respect an ecologically responsible alternative to tropical hardwood. Basically, there is no need to cut down a tree and the wood waste can just as easily bear the FSC label.
Other cladding Other producers have noticed the growth on this market. Sidings are appearing in diverse materials and not necessarily in a wood look. For instance, we also find on the market wall strips made from fibre cement, an extremely durable and ecological material. Another product on offer for new or renovated walls are sidings made from hard-foam PVC with a co-extruded top layer above. Yet another producer offers sidings made from high-quality synthetics (ABS). ABS is not porous, so it cannot absorb damp. Moreover, it is resistant to UV and therefore ensures a durable solution.
The importance of ventilation Outdoor Wood Concepts® (B) has launched a unique rafter which is an excellent solution for the ventilation issue regarding sealed vertical wall cladding. What is the problem? With vertical cladding the supporting framework (the rafters) obviously runs horizontally. And so, with continuous rafters there is hardly any connecting cavity behind the planks, so there is little ventilation, if any at all. Strictly speaking, there are two solutions for providing a well ventilated cavity for sealed vertical planks in order to prevent mould, namely single slats with openings or double
