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National Timber Systems (NTS) is to launch GreenBox® floor-cassette system – which uses lightweight, low-embodied-carbon engineered-timber – in the UK in collaboration with international engineering, design and technology firm Thornton Tomasetti.

The system can be used in new builds, extensions or renovations for commercial and multi-occupancy residential developments. It performs like a concrete floor, but with less mass and a fraction of the embodied carbon. 

GreenBox is specified for each project and manufactured to order. The stiff timber structure of the cassette has a proprietary filling of recycled non-toxic materials, which provides strong fire resistance and tunable acoustic performance.

Long-span cassettes offer architects and specifiers more design flexibility for column-free spaces and big bays, alongside the significant environmental benefits of using timber. The ceiling created by the system has an attractive wood soffit with few, if any, down-stand beams, and specialty plywood can be used instead of the standard panel if preferred.

Philip Carney, NTS Technical and Innovation Director, said: “We are excited to be manufacturing GreenBox for the UK market.

“We always aim to help our customers build more sustainable structures through innovative design and high-quality manufacturing, based on our ‘less on site’ philosophy.

“In line with that, GreenBox has been designed to be simple to install. The cassettes drop into the building frame and are screwed together from the top of the cassette, no special skills or equipment are needed on site. When it’s time to renovate or reconfigure the building the cassettes can be easily replaced, reused or recycled.

Harry Crofton, Associate at Thornton Tomasetti, said: “GreenBox is a simple way to drastically cut a building’s embodied carbon, speed construction and provide sought-after finishes.

“We’ve been talking with UK-based architects and specifiers and there is a lot of interest in GreenBox already.

“A typical building’s frame and floors can make up about half of its embodied carbon, so reductions in the floor system have a big impact.

For more information on GreenBox contact

NTS is the specialist engineered wood products division of National Timber Group.

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