Structural steel sections are typically highly robust and are bolted together, meaning they are easily demountable. However, at present most steel reclaimed from buildings is sold as scrap and melted down.
Steel is routinely recycled, but is less often simply reused, which would be much cheaper. Barriers include traceability and certification issues.
The Steel Construction Institute (SCI) has published a 46-page guide* to give the construction sector confidence to re-use structural steel, thus reducing greenhouse gas emissions as well as saving money. It provides guidance on the procedures and processes for reclaiming steel used in existing structures, and for using surplus steel, such as from cancelled projects.
The SCI protocol recommends data collection, inspection and testing to ensure that surplus steel or reclaimed structural steelwork can be reused with confidence. It is limited to steel erected after 1970; in applications where the steel was not subjected to fatigue, such as bridges; and also excludes steel damaged by corrosion, fire or high impact.
Dr Michael Sansom of the SCI said: “There is growing pressure on the construction industry to be more resource efficient and to lower its greenhouse gas emissions. Increased reuse of steel will support both of these aims and stimulate new business opportunities in the UK – in particular by substituting steel imports.”
Furthermore, life cycle analysis by consultants Giraffe Innovation shows that using surplus steel from cancelled projects can reduce greenhouse gas emissions by up to 96% compared to using newly-milled steel.
Tom Hay, director of Pluton Engineering and a member of the Institution of Structural Engineers’ sustainability panel, said: “The construction sector has been crying out for proper guidance on how to safely and effectively reuse structural steel. These protocols from the SCI should help the industry to be more sustainable and embrace the circular economy in a way it has been unable to do so due to a lack of clarity in the existing regulations. Hopefully the SCI’s approach will be adopted at a national and European level.”
Cleveland Steel & Tubes Ltd, a supplier of surplus steel for construction, supported and contributed to the report. The company specialises in supplying surplus steel – typically pipes from oil and gas projects – for re-use in construction projects. Managing director Roy Fishwick said: “These protocols should help to remove the shackles and allow construction contractors to purchase reused or surplus steel with complete confidence in its structural integrity. Our repurposed steel is proven to deliver up to 96% savings on carbon emissions compared to using new steel. It is an environmentally friendly solution as well as a cost-effective one.”
*Structural Steel Reuse: Assessment, Testing and Design Principles is available from the Steel Construction Institute website, www.steel-sci.com