Green construction has been the subject of considerable attention for some time now – but what about demolition? One innovative organisation, Taisei Corporation, is leading the charge.
The Japanese company has developed an eco-friendly process that makes it possible to salvage building materials for recycling and reuse, while also reducing CO2 emissions through effective use of energy.
The Taisei Ecological Reproduction System, or Tecorep, begins with the creation of an enclosed space at the top of a building in which everything that can be reused is removed. The system then works top to bottom, floor by floor, while the roof is held up by temporary columns lowered by jacks as the higher floors come down.
Currently, Taisei is undertaking a project of significant proportions: bringing down the 140m-high Grand Prince Hotel Akasaka, a Tokyo landmark.
The salvaged materials are transported to the ground using a crane, which in turn uses the weight of its load to generate electricity. This energy is then harnessed to power other equipment needed during demolition, such as lights. In a report outlining the system, Taisei notes that approximately 5,100kJ can be generated at the maximum weight of 8 tons. In addition, says the company’s head of construction technology development, Hideki Ichihara, carbon emissions are reduced by 85%.
So could this be the future of demolition? Jennifer Clark, Director of Environment at UK construction specialist Skanska, calls it “an interesting development”, adding: “We have been increasing recycling rates on site to lessen demolition impact for a number of years. But this is the first time I’ve seen a technique like this used – although there are a number of cranes and hoists that generate energy on the market now.”
In the US, salvaging materials for reuse is promoted through organisations such as the Delta Institute and the Building Materials Reuse Association, non-profit organisations working to advance sustainable development. Meanwhile, in the UK, regulations are planned that will require developers, builders and contractors to consider how to prevent, minimise and recycle waste when planning a demolition project. – Ruth Stokes
Photo: Flickr kobakou