The Tapered Box Beam is manufactured by folding two halves of steel plate and welding them together to form a box.

The box is tapered through its length, utilising only the amount of steel required, which reduces the weight/cost without affecting structural integrity. Using the Tapered Box Beam, spans range from 20m to 75m. An absence of knee and apex braces means more usable space within the building, and because the Tapered Box Beam is a sealed hollow section, it’s also bird-resistant, providing no surfaces for birds to roost when purlins are embedded.

The product is a joint development project between Donovan Group and New Zealand Steel.

The Tapered Box Beam has also been independently checked and verified by HERA (Heavy Engineering Research Association).  HERA is recognised in both New Zealand and abroad as a leading authority in the design of steel structures.

Visit our brochures page to download the Tapered Box Beam booklet.


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Tapered Box Beam System

Structural points of difference

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