Shell based structural forms in timber are increasing in popularity not least because they develop its unique combination of properties in a very efficient way.
This one has a span of 22m x 68m girth yet the ribs are only 300mm deep (x 75mm) and is probably best described as 'Geodesic'. It took just under 600 ribs to cover 1000m2. They were generally under 3m long and 35kg each with many repeat patterns making them much easier to process both on and off site.
The ribs were profile cut from 'Kerto' Laminated Veneer Lumber which was also used for the deck. This was bent around the 10m & 30m radii detailed across the roof section. A dense pattern of 'Ledgerlok' screws secured the 33m sheets to act compositely with the ribs thus assisting the remarkable span to depth ratio.
Kerto LVL is mostly made from Spruce. The logs are cut to 1.6m long (or short!) prior to rotary cutting the veneers. Less material is discarded resulting in much improved utilisation compared with cutting rectangles from long lengths.
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