Wood will never lose its instinctive appeal as a building material. We appreciate its natural characteristics and we have built with it, and used it to decorate our buildings for many thousands of years. We enjoy its beauty, its warmth and its texture.
Yet for architects and builders there are many drawbacks to using wood, whereas in my view metal, especially aluminium, brings significant advantages. These extend from financial and environmental benefits to superior qualities in terms of design, installation and durability.
Hardwood is expensive, and if it is imported from overseas, the final price is often not known until it is “landed”. Prices can fluctuate rapidly too. For some structural building components the wood has to be knot-free as knots are points of weakness, meaning that not all of the raw material can be used. Holding stocks of timber is a costly exercise and supplies are not easily transferable on to other projects. In comparison, aluminium is less expensive, being a highly abundant recyclable material and available in lower and higher grades, suitable for different projects. Its price is relatively stable and known in the time-frame of most projects. Holding aluminium supplies at a mill condition means that it can be rapidly converted for use in the latest project.
For design purposes, aluminium is easy to use and very adaptable. It has a high strength to weight ratio which is a huge advantage in many exterior and interior façade projects. Its weight will remain constant once installed and no tolerances have to be built-in for weight increase, which may occur when wooden structures absorb moisture. Far fewer brackets are required to install an aluminium structure compared to a wooden one, reducing the inventory and associated costs. The high strength: weight ratio of aluminium means that designs can be slim and delicate when required and the design flexibility is extensive. Finely angled, strong yet lightweight aerofoil fins for solar shading are one example.
Damage and deterioration, either pre-or post-fabrication, is more likely to occur with wood and causes bigger problems as replacement material will not be readily available. The same is true of mistakes made during manufacture. With aluminium the component can either be reformed or a fresh piece of aluminium can be substituted very rapidly.
Gaining longevity
Wood and metal need to be treated in order to survive exposure to the elements and the wear and tear of usage. Aluminium comes fully into its own when it is powder coated, gaining longevity through excellent resistance to corrosion and abrasion. In the context of this article, when Powdertech Wood Finish (PWF) is the finish chosen, designers and builders are able to combine the structural integrity of metal with the visual appeal of wood. PWF is a polyester powder-based coating designed to replicate the different grain patterns in wood and is available in thirty-five different shades. Powder coatings are environmentally friendly, as discussed in my previous article, containing no VOCs or halogens and producing no hazardous waste. Wood preservatives are a lot safer than in years gone by but handling precautions are very necessary and the chemicals used are under constant review.
PWF is colour stable for 12-15 years and often longer with no fading or sun-bleaching. Maintenance is minimal; the finish will need washing with clean water every six months to a year, depending on external conditions. Wood, on the other hand, requires painting and re-painting, varnishing or oiling and is subject to rot, mildew and warping unless a maintenance programme is strictly adhered to.
Keeping costs within budget, and for the long term, is increasingly important to major suppliers in order to improve margins and protect markets. The combination of aluminium and a powder coating finish delivers on all fronts. Manufacturing and maintenance costs are reduced and consistent, installation is rapid and environmental credentials are highlighted. By choosing PWF, any project for which wood was the original design vision can be brought to fruition, by combining the performance of aluminium with the look of wood.
Please feel free to contact us to talk about powder coatings and we will be happy to share our knowledge and experience with you.
Contact Richard Besant on 01536 400890 / richard.b@powdertech.co.uk
