System mapping of wood in construction uncovers key insights

The “Wood in Construction Systems Map,” developed by the University of Edinburgh, aims to uncover ways to increase the carbon benefits of wood fibre in UK construction. The map is part of EIT Climate-KIC’s Landscapes as Carbon Sinks Deep Demonstration in Scotland, a project aiming to help the country’s landscape systems decarbonise, adapt and increase resilience to climate change, and foster a bioeconomy—the sustainable extraction and production of natural resources, like wood.

The Scottish Government has a commitment to tree planting targets to increase total forest land area from 19 per cent to 21 per cent by 2032. However, combining forest growth with sustainable wood harvesting for long-term construction products can increase the overall carbon removed from the atmosphere and mitigate the risk of climate change, disease and pests to the forest carbon store. According to an Intergovernmental Panel on Climate Change (IPCC) report on forestry: “Mitigation options by the forestry sector include extending carbon retention in harvested wood products, product substitution, and producing biomass for bio-energy. This carbon is removed from the atmosphere and is available to meet society’s needs for timber, fibre, and energy.” 

The benefits of using wood in construction include storing carbon within buildings and displacing high-carbon materials like cement, brick and steel. Specifically, timber frame buildings store 50 per cent more carbon than an equivalent masonry structure and buildings made from cross-laminated timber store 400 per cent more carbon than concrete ones.

The Landscapes as Carbon Sinks Deep Demonstration team looked at what is currently enabling and inhibiting the use of wood from Scottish forests in the UK construction sector. To bring these findings to life, Galina Toteva and Hester Robertson of the University of Edinburgh created the interactive “Wood in Construction System Map.”

The map shows the causes and effects of key forces in a system, exploring how they connect in causal loops and how these loops interact with one another. It aims to answer the question ‘why is the system the way it is?’ or in this instance ‘why, given its clear environmental benefits, is the use of wood in construction not more prevalent?’ The map is not meant to be a complete catalogue of everything that influences the system. Instead, it aims to display the most important areas of focus that are key to answering the question.

Why, given its clear environmental benefits, is the use of wood in construction not more prevalent?

1. A knowledge gap across the construction timber supply chain

In order to achieve a 50 per cent increase of Scottish wood in construction the industry needs to be specifying for timber. This requires architects, structural engineers and the wider industry to be trained in timber construction techniques and for the wider public to see timber as a desirable building material.

2. Traditional construction dominates

The current construction market is dominated by a few players, with established relationships and supply chains, who use traditional construction methods where timber plays a minor role. These companies’ ability to change practices is constrained by client preferences, and supply chain restrictions. Culture and risk are barriers to investment and adoption of innovative practices. Without confidence in the growth of the market for timber products investors will not invest in the facilities, training, and technology necessary for this growth.

3. Local timber supply constraints

Fundamental to achieving a 50 per cent increase of Scottish wood in construction is the availability, quality and range of UK timber for construction. In turn, architects and structural engineers need to design and specify timber components to match the properties and availability of local material.

4. Siloed professions

Planting targets and hence timber availability are underpinned by land use strategies. Currently, strategies in Scotland are highly siloed.

Landscapes as Carbon Sinks is one of eight Deep Demonstrations launched by EIT Climate-KIC, which together offer examples of the ambitious, “1.5°C-consistent systems transitions” called for by the IPCC reports, climate scientists, activists and European policymakers. Deep Demonstrations of turning landscapes from carbon sources to sinks tackle a lack of investment, as well as the need to forge new social contracts with soil and forests and line-up value-chain incentives. Current partners include Chalons-en-Champagne, a French landscape ecosystem, and the Government of Scotland.

The Scottish Landscapes as Carbon Sinks Deep Demonstration is a collaboration with the Edinburgh Centre for Carbon Innovation (ECCI) and the University of Edinburgh’s Centre for Sustainable Forests and Landscapes (CSFL).

Visit the full “Wood in Construction Systems Map.”

Explore the map