RHS GARDEN BRIDGEWATER
A WELCOME ADDITION TO SUSTAINABLE CONSTRUCTION
01 RHS Garden Bridgewater is the largest gardening project in Europe with its new Welcome Building showcasing a number of different timber construction components and techniques to award winning acclaim. The Royal Horticultural Society (RHS) is the world’s leading gardening charity, inspiring passion and excellence in the science, art and practice of horticulture. In November 2015, the RHS, in collaboration with Salford City Council and Peel Land and Property, announced the vision to create the new garden at the site of the 154-acre Worsley New Hall estate. RHS Garden Bridgewater will become a major new tourism and horticultural destination which aspires to welcome and inspire up to 700,000 people a year within a decade.
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The new ‘Welcome Building’ saw Hodder + Partners invited to design a new world-class visitor centre providing a gateway to the gardens as well as a visitor meeting and interaction point, restaurant, gift shop, offices and educational spaces. The Welcome Building has been delivered by BAM as the main contractor with HESS TIMBER providing the engineering, production and assembly of the structural timber elements. The Welcome Building is designed predominantly as one open space, allowing the visitor to flow between the various uses and functions: ticketing, a learning centre, retail area, indoor plant sales and café. All of these public elements are contained under a single overarching timber diagrid roof, supported on structural glulam timber columns, allowing the space to flex in response to seasonal demands. The roof structure consists of three different timber construction components: ‘cigar-shaped’ glulam columns, timber diagrid cassettes with diagonally arranged inner grillages and a straight
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outer glulam timber rafters, as well as cross laminated timber (CLT) panels to tie the cassettes together. The sanded ‘cigar-shaped’ glulam timber columns rest on 16 reinforced concrete columns, each of which has a diameter of 450 mm. The glulam timber columns measure 3850mm in length and 300mm in width (in their centre) and are tapered to 200mm at both ends to ensure an attractive, filigree and light overall appearance of the roof construction. The columns are structurally relevant and support the entire roof, which measures 2160m in total. The timber diagrid consists of individual cassettes dividing the whole roof into 6m grids. Each individual cassette measures 6m x 3m and consists of diagonally arranged inner grillages and straight outer rafters which provide stability and bracing to the whole roof structure. Natural light permeates the building either through Siberian Larch louvred curtain walling or filters through the diagrid roof via two roof lights, one
