Chris Leese, Director MPA UK Concrete, comments on the decision by one east London Borough to switch from timber to concrete in a residential development.
The London Borough of Newham has made a common sense design decision, as Red Door Ventures, the Council’s housing company, has replaced timber as the primary structure of the ‘The Brickyard’ scheme with concrete.
The government has already banned the use of combustible materials in the external walls of blocks of flats above 18m – including cross laminated timber (CLT). Unlike non-combustible materials such as concrete which does not burn, the dangers of combustible materials are well known. When exposed to fire, timber burns, leading to the risk of toxic fumes filling flats and apartments, while diminishing the structural integrity of the property – heightening the danger for residents.
Moving away from timber is a well-reasoned response to the dangers of combustible timber properties. Indeed, the Association of British Insurers (ABI) has called for an end to the use of all but non-combustible materials in construction.
Newham’s decision in some quarters was met with questions regarding the carbon impact of concrete. It’s important to understand the facts. Concrete is locally sourced, and 100 per cent recyclable at the end of its life. The whole-life performance of concrete buildings over their long lifetimes can offset the impact of their construction through superior energy efficiency and reduced maintenance requirements.
The material will play a vital role in meeting the UK’s ambition of net-zero carbon emissions by 2050.
The cement industry is switching from fossil fuels and actively researching net zero fuel mixes, and as a whole the cement and concrete industry is decarbonising faster than the UK economy, having delivered a 53% reduction in absolute carbon emissions since 1990.
The decision by Newham to review the specification in light of the risks posed by CLT is significant and appropriate.
Using concrete to protect against fire is a responsible design decision, especially for multiple occupancy buildings such as flats, hotels and student accommodation and those with vulnerable occupants including schools, hospitals and care homes.