The group of engineered solid wood products known in the UK as ‘mass timber’ demonstrate enormous potential for carbon reductions in major developments, due to their structural strength, versatility, lightness, high degrees of precision and low-carbon manufacturing. These attributes mean that mass timber products are technically suitable for structural use in medium and high-rise buildings, as demonstrated up to 24 storeys in Austria, 18 storeys in Norway and Canada, and 10 storeys here in the UK.
‘Mass timber’ is an umbrella term given to the family of engineered wood products that comprise multiple pieces of timber that are layered, or laminated, into solid wood elements for structural application. Mass timber includes Cross Laminated Timber (CLT), Glue Laminated Timber (Glulam), Laminated Veneer Lumber (LVL) and Dowell Laminated Timber (Brettstapl or DLT).
The carbon reduction benefit has been identified as the main driver to the adoption of mass timber in buildings. This project does not intend to detail these carbon benefits, as this topic has been explored extensively elsewhere. For further information regarding timber’s role in tackling the climate crisis, see publications from the Cambridge Centre for Natural Material Innovation or Forestry and Land Scotland. For up-to-date embodied carbon factors of mass timber products, refer to the December 2021 article by IStructE comparing EPDs from all the major European producers of mass timber
Mass timber products can be used for the entire structure of a building, or in a ‘hybrid’ or ‘mixed’ structural system. A ‘hybrid’ structure uses a combination of mass timber and other materials throughout a structural system; CLT floor slabs within a steel frame, for example. A ‘mixed’ structure is one where two or more structural systems are used in tandem; A concrete stair core and ground floor combined with a Glulam post and beam frame with CLT floors, for example. The ‘challenges’ we speak about here are experienced when using any one of these types of structure.
 HoHo, Vienna, Austria. Completed 2019. Project information available online from BuildUp EU. Link: https://www.buildup.eu/en/practices/cases/hoho-vienna-first-city-office-built-timber-vienna
 Brock Commons, Vancouver, British Columbia. Completed 2017. Project information available online from ThinkWood. Link: https://www.thinkwood.com/projects/brock-commons-tallwood-house
 Forestry & Land Scotland, Scottish Government, https://forestryandland.gov.scot/what-we-do/timber-industry/timber-and-the-climate
 IStructE, Mass Timber Embodied Carbon Factors https://shop.istructe.org/resources/blog/mass-timber-embodied-carbon-factors/