Rockingham-based Pryda Australia fabricator WA Spantruss designed triangular box trusses for a covered courtyard in John Septimus Roe Anglican Community School at Mirrabooka in Western Australia.
Used for the first time to overcome access limitations, the trusses were designed using Pryda Build by the fabricator WA Spantruss, assisted by Pryda’s Market Development Engineer Bernard Kennelly based on a brief from the architects Brooking Design.
The $1.1 million D Block enclosure construction presented a comprehensive challenge because of its location between two adjacent brick structures. A key objective was to restrict noise transfer among all three spaces, especially since up to 190 students would be potentially using the spaces at any given moment. 

The award-winning Brooking Design specialises in school architecture with more than $10 million worth of projects currently in design or under construction. Recently recognised for its work on the John Septimus Roe Kindergarten in Beechboro WA by the Western Australian chapter of the Australian Institute of Architects, the Australian Interior Design Awards and Dulux Colour Awards, Brooking Design has used Pryda fabricators in the past to solve complex truss design issues.
The John Septimus Roe Anglican Community School required the Nordic style courtyard design to match the previous kindergarten project Brooking Design had completed at the venue; the use of timber, insulation and natural lighting was also essential to meeting sustainability requirements.
WA Spantruss designed and supplied 9.2-metre long double parallel girder trusses for each of the 14 portals or panels needed to cover in the courtyard, all supported 4.8 metres above the ground by laminated LVL timber beams. The timber columns, trusses and plywood forming the construction of roof and walls contributed to a significant reduction in noise transfer. 

The use of the triangular box construction (where two truss sections were connected together) allows light panels to be included in the roof while also creating an aesthetically pleasing and interesting geometric form that bathes the internal space in diffused sunlight.
When combined with the padding between the double timber stud wall frames, the triangular box trusses not only significantly reduce reflected noise, but also provide improved insulation. The triangular box sections contributed to the successful completion of the project because it resulted in a lightweight, rigid structure that only needed common fixings, which could be quickly and easily used on site without any special skills required. Additionally, the triangular boxes could easily be formed on site in a confined space by two or three carpenters and then lifted into place by a very small crane. 

The triangular box trusses have significantly contributed to achieving the project’s objectives of restricting noise transfer, providing access to natural light, improving insulation qualities and ensuring speedy onsite erection.