海角视频

The construction sector must undergo significant decarbonisation efforts, guided by a number of key strategies to achieve a sustainable future 鈥� and a sustainable built environment industry.

Thorough Life Cycle Assessments (LCA), building energy efficiency, and tackling both operational and embodied carbon, we have the power to make a change. Associate director and climate champion in our Warsaw office, Wiktor Kowalski, explores four key strategies in reducing carbon emissions across a building’s life cycle.  

With the construction sector accounting for , a reduction of emissions stands at the forefront of the battle against climate change. To reduce the carbon footprint of buildings, significant measures are required, but selecting appropriate solutions must be preceded by a thorough diagnosis. Decarbonising the construction sector necessitates actions across multiple areas, although not all measures will be equally effective for every building. By implementing innovative strategies and leveraging advanced technologies, we can significantly reduce the wider sector’s carbon footprint and pave the way for a sustainable future. 

A Life Cycle Assessment (LCA) enables the identification of solutions that yield the greatest benefits throughout the building’s life span, considering the specific characteristics of the building. Conducting an LCA at an early project stage and evaluating various emission reduction strategies can guide projects towards more sustainable outcomes. 

Collaboration among stakeholders

Decarbonising the construction sector is a multifaceted challenge that requires collaboration among various stakeholders. Architects play a crucial role by designing energy-efficient buildings and incorporating sustainable materials, thus reducing embodied carbon.

Engineers are pivotal in implementing innovative technologies such as low-carbon concrete and renewable energy systems, ensuring that buildings not only meet structural requirements but also contribute to lower emissions. Developers are responsible for driving demand for green buildings and investing in sustainable construction practices, which can enhance market value and attract eco-conscious investors.

Lastly, building occupants have a significant impact by adopting energy-saving behaviours and supporting policies that promote sustainability, thereby contributing to the overall reduction of operational carbon. Together, these stakeholders can create a synergistic approach to decarbonising the construction sector, paving the way for a more sustainable future. 

Building energy efficiency

In the context of reducing operational carbon footprints, decarbonising the energy grid is crucial. However, for both existing buildings commissioned in the past decade and newly designed structures, numerous opportunities exist to minimise greenhouse gas emissions. 

Older buildings can significantly reduce their carbon footprint through modernisation efforts aimed at minimising heat loss. Replacing windows, insulating external walls and implementing heat recovery from ventilation are actions that substantially reduce energy consumption for heating. For newly designed buildings with high energy efficiency, further emission reductions can be achieved by considering the use of air or ground source heat pumps. These devices, powered by “green” electricity, can significantly lower carbon dioxide emissions. 

In regions where the energy mix does not yet heavily rely on renewable sources or nuclear energy, on-site production of “green electricity” may be necessary to power heat pumps. Where on-site photovoltaic installations are not feasible, purchasing a certificate of origin for energy produced elsewhere, such as from wind farms, can be considered. Unfortunately, while this improves the operational carbon footprint of individual buildings, it does not alter the emission balance for the entire construction sector. This is because the “clean” energy sold with a certificate of origin guarantee is not included in the energy pool supplied to the grid for other consumers, resulting in proportionally higher emissions for neighbours in buildings powered without the certificate. 

Operational carbon footprint

Further reduction of the operational carbon footprint may be achieved by analysing aspects such as shading, building orientation, glazing characteristics and the potential use of renewable energy. It is best to embark on such a strategy at the early stage of the design and optimise it through subsequent design stages. 

For instance, it is possible to develop a facade design based on results from the energy model, with multiple factors such as percentage of glazing, light transmittance coefficient, shading elements and thermal properties of opaque enclosures. Only then can the facade be considered as optimised from all angles 鈥� using daylight potential while reducing heat losses and the demand for cooling. 

Embodied carbon footprint

The upfront carbon footprint of a building encompasses the sum of greenhouse gas emissions associated with material production, transportation to the construction site and emissions at the construction site itself. The upfront carbon, along with emissions associated with repairs, maintenance, replacement and demolition and waste disposal are collectively known as the embodied carbon footprint.

With the implementation of the EU , which mandates organisations to report emissions throughout the supply chain, the embodied carbon footprint is gaining importance. In the coming years, all EU member states will need to include restrictions on the embodied carbon footprint in building regulations, such as current limits on the annual energy demand indicators for buildings. Such limits are already in place in different forms in some EU member states, e.g. in Denmark. 

Regulations aimed at reducing greenhouse gas emissions can significantly impact how and from what materials buildings will be constructed in the coming years. To comply with future regulations with restrictions on the “carbon budget”, novel materials and construction techniques will need to be adapted. Building parameters such as column spacing and number of underground floors may determine whether a building meets future requirements or exceeds the threshold values of the carbon footprint, therefore early evaluation of design options is needed when developing a building concept.  

Usually, the major contribution of the building鈥檚 embodied carbon is its structural frame and foundations but to achieve a significant reduction of the carbon footprint, all building components should be reviewed from this angle. Only a holistic strategy, established at the beginning of the design process, will keep the carbon footprint in check.