Sustainable development consultancy Arup has released new global guidance on how to build fire-safe mass timber structures in the hope of encouraging more widespread deployment of this low-carbon alternative to concrete and steel.
The guide sets out an evidence-based approach to support and plug gaps in local country codes and regulations, to assist in the fire-safe design of mass timber buildings. While the USA, Canada, Australia and several European countries have mature timber construction industries, supported by a regulatory framework and design codes, many other countries are earlier on in their journey.
Advertisement
The report’s authors believe that the lack of clear and consistent guidance globally is holding back uptake of this important low-carbon construction material. The risk-based guide will help fire safety engineers, structural engineers, architects, developers, local authorities, insurance companies, property owners, and project managers exploring the use of mass timber to answer essential questions such as which fire safety measures are required to address the specific fire hazards posed by mass timber; can all mass timber remain exposed or where does it require encapsulation; what fire performance and specification is appropriate for the mass timber components, is a single-stair building compatible with safe mass timber construction; and should mass timber be employed in the construction of external walls?
Arup is sharing its internal guidance as part of efforts to reduce carbon emissions to help reach the UN goal of making near-zero emission buildings the new normal by 2030. Research by Arup and the World Business Council for Sustainable Development has shown that of the embodied carbon associated with construction, 70 per cent comes from six materials, including concrete and steel. Using more sustainable materials such as timber in the right way has the potential to dramatically reduce this figure.
Advertisement
The new guidance draws on decades of Arup involvement in research and design on fire safety engineering for mass timber structures; this expertise has been used to inform the development of several landmark projects, such as the Sky Believe in Better Building in the UK and the Galkangu Bendigo GovHub building in Australia.
Most recently, Arup has conducted some of the largest timber fire safety experiments in the world. The Code Red research project in France saw a series of full-scale fire experiments in a 350-square-metre compartment with mass timber ceilings to help the industry better understand how fires would grow, develop and decay in an open-plan space such as an office. Arup is also contributing to the development of codes and standards around the world.
Advertisement
The guide focuses on building typologies where mass timber has the greatest potential – office and residential buildings up to 50 metres tall and educational buildings up to 25 metres tall. Often, the sustainability benefits of mass timber structures diminish as the building height increases.
However, the guide and its underlying research has also helped to inform mass timber buildings above 50 metres in height, such as the Netherland’s timber-hybrid residential building Haut, and the 86.6-metre-tall luxury apartment and retail tower Ascent in Wisconsin (pictured above), the tallest mass timber building in the world.
‘As well as gaps in codes and regulations, there is also a lack of knowledge among much of the design and construction community when it comes to designing fire-safe timber buildings,’ said Judith Schulz, fire safety engineering lead at Arup. ‘This means the opportunities for more sustainable construction are not currently being realised. We hope this guide will contribute to accelerating a move away from carbon-intensive materials and contribute to a growth in fire-safe mass timber buildings, which offer great promise for reducing CO2 in low- to medium-rise buildings.’