Mitigating carbon emissions of single-family houses: Assessing the need for a limit value

Reducing carbon emissions in the global building and construction sector is a crucial part of achieving climate targets. Laws that aim to limit the carbon emissions of new buildings have yet to be implemented on a larger scale, although some nations already have thresholds. These thresholds may not be sufficient to mitigate carbon emissions, and not all types of buildings are obliged to comply with them. In the case of Denmark, single-family houses (SFH) are not required to not comply with a limit, although they represented approximately 17% of all newly built areas from 2010 to 2022, indicating significant resource use and associated carbon emissions. This study aims to establish sufficient background data to support the need for implementing a limit value for SFHs in building regulations to ensure necessary reductions in carbon emissions. The study finds that the life cycle carbon emissions of Danish SFHs vary between 5.6 and 13.2 kg CO2e/m ²/year, showing that compliance with the current limit value of larger buildings is possible and that a reduction of more than 50% in carbon emissions is possible. However, currently, there is no intentional investigation or achievement of potential carbon emissions in the construction industry. The study’s findings inform policymakers that a limit value for SFHs must be introduced no later than 2025 to initiate the necessary reduction of carbon emissions.