Emission Omissions: Carbon accounting gaps in the built environment

The report argues that current LCAs for building materials often lack transparency and omit critical data, particularly regarding biogenic carbon in wood and operational emissions. It concludes that for energy-efficient, long-lived buildings in Canada, the choice of structural material has a negligible impact compared to operational efficiency, and recommends prioritizing building longevity and energy efficiency over material substitution.

• Life-cycle assessments (LCAs) for building materials often produce inconsistent results because assumptions and uncertainties are typically not fully disclosed, and sensitivity analyses are rarely performed to determine how these assumptions affect the outcomes.
• Many LCAs overstate the importance of embodied emissions by ignoring operational stage emissions and other building systems, such as heating, ventilation, and site preparation.
• Regional factors significantly influence life-cycle emissions; for instance, sourcing steel from Canadian electric arc furnace (EAF) mills can reduce embodied emissions by two to four times compared to basic oxygen furnace (BOF) mills or imports from China.
• The accounting of biogenic carbon in wood products is a major source of uncertainty, as many LCAs assume carbon neutrality while ignoring soil disturbance, conversion of old-growth forests, and the fact that as little as 15 per cent of a tree's carbon may be sequestered in the final product.
• Sensitivity analyses indicate that if factors like soil carbon loss, primary forest conversion, and a 90 per cent silvicultural success rate are considered, the cradle-to-gate emissions for wood buildings increase by 5 to 72 per cent, potentially making them higher than concrete buildings.
• In the context of energy-efficient and long-service-life structures in Canada, the GHG impact of choosing one building material over another is negligible, meaning operational efficiency should be prioritized over embodied emission reductions.

APA

Stiebert, S., Echeverría, D., Gass, P., & Kitson, L. (2019). Emission Omissions: Carbon accounting gaps in the built environment. International Institute for Sustainable Development. https://www.iisd.org/system/files/publications/emission-omissions-es.pdf

Chicago

Stiebert, Seton, Daniella Echeverría, Philip Gass, and Lucy Kitson. Emission Omissions: Carbon accounting gaps in the built environment. International Institute for Sustainable Development, 2019. https://www.iisd.org/system/files/publications/emission-omissions-es.pdf.

Wikipedia

{{cite report |last1=Stiebert |first1=Seton |last2=Echeverría |first2=Daniella |last3=Gass |first3=Philip |last4=Kitson |first4=Lucy |title=Emission Omissions: Carbon accounting gaps in the built environment |publisher=International Institute for Sustainable Development |date=April 2019 |url=https://www.iisd.org/system/files/publications/emission-omissions-es.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stiebert2019emission, author = {Stiebert, Seton and Echeverría, Daniella and Gass, Philip and Kitson, Lucy}, title = {{Emission Omissions: Carbon accounting gaps in the built environment}}, institution = {International Institute for Sustainable Development}, year = {2019}, month = apr, url = {https://www.iisd.org/system/files/publications/emission-omissions-es.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }