The global guide, from global sustainable development consultancy Arup, 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 US, 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.

Authors of the new report 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?

  • 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 (WBCSD) has shown that of the embodied carbon associated with construction, 70% 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.

The Fire Safe Design of Mass Timber Global 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 many 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 m2 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 offices. Arup is also contributing to the development of codes and standards around the world.

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 inform mass timber buildings over 50 metres such as the Netherland’s tallest timber-hybrid residential Haut and Ascent, the tallest mass timber in the world in the US.

Key benefits of timber buildings include:

  • Sustainable and zero-carbon – appropriate use of timber can significantly reduce the carbon footprint of many types of buildings and contribute to limiting the carbon emission contributions of the wider construction industry.

  • Faster and quieter – the use of timber is well-suited to construction in dense urban environments. It is lightweight enabling less road deliveries and is also quiet and quick to assemble. This can help reduce construction noise, time and disruption.

  • Reduced waste – timber produces less waste because it can be prefabricated off site. New digital fabrication technologies enable timber buildings to be constructed very efficiently; where timber can be left exposed it avoids time and cost of applying finishes.

  • Well-being – there is a positive impact of timber on human well-being. Integrating wood into buildings can create a warn and natural environment, enhancing occupants’ comfort and well-being.


* UN Environment Programme: 2022 Global Status Report for Buildings and Construction

** UN The Buildings Breakthrough: Global push for near-zero emission buildings by 2030

*** Net zero buildings: where do we stand, Arup and WBCSD