4.1 Scaling Renewable Building Materials: Opportunities and Challenges



to Bio-Based Building Materials

Moving towards more renewable materials requires sustainable resource management and incentivizing biodiversity.

© Steve Proehl / Getty Images

Chapter 4
Scaling Renewable Building Materials: Opportunities and Challenges
Timber and Wood

Figure 4.1 Historical development of atmospheric carbonpatterns

A shift to bio-based building materials by 2060 can replenish the carbon pool and reduce atmospheric carbon

The figure shows the historical transition in the terrestrial carbon pool from formation (left) to depletion (middle) to gradual replenishment (right, with simultaneous reduction in atmospheric carbon). Adapted from Churkina et al. 2020.

Scaling Renewable Building Materials: Opportunities and Challenges

Renewable bio-based building materials can drive reductions in atmospheric carbon.

If managed responsibly, renewable bio-based building materials have a unique capacity to drive reductions in atmospheric carbon by: 1) matching renewable resources to building material applications, at lower carbon footprints, and 2) serving as a global carbon sink (see Figure 4.1). Timber is the leading bio-based building material being used at scale. Although promising technological product innovations are available to address rising demand for timber in developed countries, demand outpaces forest regrowth and relies on a limited range of tree species (Pomponi et al. 2020). Global timber demand has a large impact on tropical forests, especially since many tropical countries do not have sufficient financial and infrastructural resources to improve material efficiency and sustainable forest management.

More policy support is needed to encourage the use of waste biomass in building materials.

A promising avenue to alleviate pressure on timber resources is the development and use of reconstituted wood products from non-timber lignocellulosic residues from forestry, agricultural and food “waste.” Today, most of the biomass from agricultural by-products is either abandoned on land (generating greenhouse gas emissions through natural decomposition) or burned (releasing carbon directly to the atmosphere). Within forests, excess biomass residues can feed and exacerbate wildfires (Sahoo et al. 2021). Meanwhile, in urban areas, waste biomass is typically either landfilled or combusted for energy recovery, both of which are more carbon-intensive pathways than converting this waste into valuable building materials (Tripathi et al. 2019; Lan, Zhang and Yao 2022). Scaling biomass residues from agriculture requires a biodiverse and material-efficient approach to avoid worsening the negative environmental and labour impacts of monoculture agriculture.