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Timber structures Wood Awards winner

The timber structure

The main hall structure is a series of remarkably slender glulam portal frames, 500mm wide but only 80mm thick, yet with columns that reach 7.5m in height and beams that span more than 10m. Drawing of the main hall. Drawing: Neue Holzbau To achieve such slenderness, the Swiss manufacturer Neue Holzbau selected spruce lamellas that were of the highest quality of strength class, as well as the highest visual grade (the frames are finished with a white translucent stain). The portal frames support paired edge beams, each 450mm x 200mm, which in turn support the roof structure, a set of deep glulam trusses, spaced at irregular intervals to achieve the necessary openings for the acoustics and ventilation strategies. Four 480mm x 240mm glulam columns stand at the corners of the structure to reduce horizontal deflection. The glulam portal frame beam and columns are connected by concealed joints using GSA® Technology, a proprietary connection system developed by Neue Holzbau. The system uses threaded rods glued to the timber and secured with epoxy resin, resulting in a concealed, protected and fire-proofed connection. Neue Holzbau designed, supplied, delivered and installed the timber structure.

The spiral staircase

The timber spiral staircase rises 8m from the mezzanine. Photo: Alan Williams

A timber spiral staircase rises more than 8m from the mezzanine to give access to the roof. It has a diameter of 1580mm and the treads are constructed of steel plate overlaid with ash veneer. The balustrade is of 25mm-thick ash veneered plywood with a solid ash handrail. At the base of the staircase is a stair gate in ash veneer with concealed hinges and lock.

Sustainability The project is part of the North West Cambridge Development commissioned by the University of Cambridge. The university undertook to make the development an exemplar of sustainability. As part of that brief all projects in the development had strict criteria to uphold, including sustainably sourced products. In addition, the project was to achieve BREEAM Excellent. The project has surpassed this goal and achieved BREEAM Outstanding for the Community Centre and Excellent for the Nursery, with the extensive use of timber contributing to the result. All the timber used is PEFC and FSC certified. The volume of the hall allowed a passive ventilation strategy to be incorporated using a stack effect. Fresh air is drawn through a labyrinth below the floor and extracted at high level through openings in the timber ceiling.

Awards Wood Awards 2018 – Mears Group Gold Award and Commercial & Leisure Award RIBA Stirling Prize 2018 – Shortlisted RIBA National Award 2018 – Winner RIBA Sustainability Award 2018 – Winner RIBA East, Building of the Year 2018 – Winner AJ Architecture Awards 2018 – Finalist

Project information Completion date: January 2018 Building type: Community centre and nursery Location: Cambridge Client: University of Cambridge Architect: MUMA Structural, civil and services engineer: AECOM Main contractor: Farrans Construction Ltd Structural timber design, supply and installation: Neue Holzbau, Switzerland

Joinery: C W Fields & Son, Yorkshire Timber supplier: Brooks Bros (solid oak), D F Richards (oak and ash veneers)

Timber elements: Main hall structure, internal wall and ceiling panels, pitched roof, cloister soffits

Timber species: Swiss spruce, European oak, American white ash, western red cedar

Further information For further information and to download the complete case study, go to Timber 2019 Industry Yearbook

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Profile for BM TRADA

Timber 2019 Industry Yearbook  

The annual publication of the Timber Research and Development Association (TRADA) includes topical and technical features on all aspects of...

Timber 2019 Industry Yearbook  

The annual publication of the Timber Research and Development Association (TRADA) includes topical and technical features on all aspects of...

Profile for trada