Woodform were engaged by Hassell Adelaide to assist in a major project at the Adelaide Zoo. The project has won 26 awards; illustrating how solid timber can successfully be used in a large-scale and serviceable manner. Adelaide Zoo. Spotted GumImage Taken in 2009 Tasked to provide detailing assistance, Woodform consulted on timber sizing, availability and the multiple applications of Spotted Gum being used in the project. Special attention was paid to long-term performance, and how the effects of weathering on the timber might impact on the design intent over the life-cyle of the building. Design Intent: Marrying the Bush with Modern Architecture Hassell architect Alex Hall chose Spotted Gum for its beautiful tones and durability; a naturally weathering finish designed to marry the bush-feel of the surrounding habitat with striking modern architecture. The result is a distinctive building that has become an award-winning Adelaide landmark. Image Taken in 2009 Materials and Treatment The main area of application was the Spotted Gum 135x32mm external blades, which were applied to the open façade screen that dominates the entrance and administration building. Adelaide Zoo By Hassell Prefabricated supporting steel work was erected and the blades were supplied in the required length range, profiled with a small chamfer on all four corners and pre-oiled in Cutex CD50. The blades were cut to length on-site and bolted into place on the steel frames. Adelaide ZooImage Taken December 2014 Additionally, an area of Spotted Gum Expression Cladding was applied to the sides of the new panda enclosure above the viewing windows; timbers for a pergola, small bridge and hand rails were also used in the same area and large mullions were used to support glazing around the shop. Meeting the Brief: Detailing and Durability The first consideration was the species choice of Queensland Spotted Gum, which is darker in colour and denser than the lighter species grown on the coastal regions of New South Wales. Long-term this provides increased longevity, and a superior weathered finish with better colour consistency. Of particular note was the protection of the endgrain of the blades on the facades. As seen in the photos, the top edge is protected by the steel angle; at the middle express joint the architect has run the steel member at a steep angle, allowing for drainage and protecting the top edge of the blades below. Image Taken December 2014 Although Spotted Gum is very durable it does have significant movement, and consideration had to be made of the extremes of the Adelaide climate; with big swings between wet and hot/dry weather in its annual cycle. Results and Performance Recent photos illustrate that there is no question about the structural integrity of the timber, and its performance over the years has been in-situ. Spotted GumImage Taken December 2014 In terms of the finish, there does appear to be some darker sections that could be the result of mildew: reapplication of the preservative Cutek is recommended to control or eliminate the mildew. This would reduce unsightly discolouration and eliminate or reduce the risk of rot.