Bent and Curved Glass (BCG) manufactured curved glass gutters for the roof of the Green Square Community Creative Precinct in Sydney. For BCG, this challenging project for the ‘Outdoor Room’ structure at the Green Square Community Centre was yet another example of what can be achieved in architectural glass.

Designed by Peter Statchbury Architecture, the concept proposed a lineal skylight system that also doubled as gutters servicing a roof area of 280sqm. This was no ordinary roof – it was created by seven undulating curved copper clad barrel vaults and required six curved gutters to form a reverse curve sitting neatly between each barrel.

Glass was the preferred material to achieve the functionality and aesthetics sought by the architects.

The challenge for BCG was to achieve a 180-degree bend with flat tangent legs extending up to the roof flashing line. The glass needed to be manufactured within tight dimensional tolerances to ensure the water tightness was maintained while achieving maximum light penetration to the area below. The gutter was required to be trafficable for cleaning purposes and the end-to-end joints needed to remain flush to achieve the required water flow.

There were several challenges of a technical nature in the manufacturing process. Each panel was hand-cut along its length to a raking profile to accommodate the fall required for the rainwater to make its way to the outlet formed by a 150mm diameter hole in the end panel. The end panel was also hand-cut around the curve to the 45-degree spout profile mirroring the splayed end profile of the roof barrels.

BCG tested a prototype to confirm the dimensional accuracy and aesthetic characteristics sought by the architects. The success of the prototype led to the completion of a truly unique glass project, with the installation managed by Lahey Constructions Pty Ltd.

Photographer: Michael Nicholson