Low carbon
facades

Sustainable approach

We are living in a Climate Emergency.

The construction industry plays a crucial role in reducing global carbon emissions; a radical change of culture in the world of architecture and construction is required to achieve the level of CO2 reductions compatible with a maximum 1.5°C global temperatures rise advised by the IPCC.
Recognising the importance of buildings’ façades in regulating operational energy, acknowledging the fundamental role of embodied carbon, and with the awareness that a ‘business as usual’ approach will not deliver the necessary savings, in recent years FMDC adopted a new design attitude where carbon is at the centre of every decision. This aligns with our clients’ sustainability agendas and the wider industry’s shift towards low carbon buildings. 

 

Façade design for energy demand reductions

When it comes to energy modelling, in recent years we have witnessed a much welcome shift away from a simple ‘building regulation compliance’ approach to a more detailed ‘design for performance’ one. This has been supplemented by strict energy intensity targets moving towards ‘net zero’ buildings, and by the adoption of performance-based rating schemes such as NABERS.

The role of façades in reducing operational carbon is inevitably interconnected with the wider approach to a building’s energy efficiency. Regulating energy demand via passive or active measures, while ensuring that the occupants’ thermal and visual comfort can be achieved is a subtle balance of conflicting requirements and inter-dependent factors that façade design needs to fulfil.

FMDC’s highly skilled and experienced building physics team can efficiently assess all aspects of façade performance that influence energy and comfort. Our strategy for identifying the right solution for each project is based on striving to find to the simplest possible design that allows all requirements to be met. Conscious that collaboration between architect, building services engineer, and façade engineer is the key to a successful holistic approach, we place great value in establishing and maintaining mutual trust within design teams and with key collaborators.

In an effort to further expand our services, in recent years FMDC formed a strategic alliance with Inform Design, a Swedish-based specialist practice who supports our work with advanced parametric energy modelling of façades. This allows us to evaluate large sets of options, quantify their impact on solar gains, daylighting, and internal comfort, and develop mitigation strategies. Another service that we can offer through Inform Design is the accurate modelling of complex façade systems such as double skin façades or CCFs.

Whole Life Embodied Carbon

Understanding, calculating, and reducing the whole life embodied carbon of buildings has been the focus of the construction industry in recent years, and as a consequence also of the façades industry. September 2022 saw the publication of ‘How to calculate the embodied carbon of façades: a methodology’ by the CWCT (Centre of Windows and Cladding Technology), a landmark document which established a consistent approach across the UK façade industry.

FMDC team’s detailed knowledge of materials, processes, manufacturing, and installation of cladding systems gives us the confidence to calculate their embodied carbon emissions with the required detail and accuracy. We can assess all lifecycle stages from individual products to assembly, from manufacturing to installation, from maintenance to replacement, all the way to end of life. This is not a trivial exercise, and it’s one that has been underestimated in the past. 

By maintaining close relationships with sub-contractors and system / material suppliers, we constantly keep abreast of the latest ‘low carbon’ technologies and options that the market can offer. This, in combination with a commitment to efficient design, allows us to provide accurate advice on potential measures to reduce embodied carbon, taking into account any technical or procurement limitations associated with specific materials.

Finally, we understand the role of façades in the greater contexts of Whole Life Carbon Assessment of buildings. The trade-off between operational and embodied carbon is of key importance, with façades influencing both. ‘Carbon payback periods’ will become a necessary tool to evaluate the impact of important façade design decisions

 

Circularity, material re-use, and recycling

We are aware that to deliver the ‘whole life’ net zero ambition the industry will need to look beyond the service life of building elements and think about how we can re-use or re-cycle them in the future, with the aim to create a circular model. The barriers to wide adoption of circularity principles in the cladding market are many, with solutions implying a change of attitude that involves a deep re-think of traditional economic and supply systems. While at FMDC we fully support the longer term transition of the industry from linear to circular, we also try to focus on what we can do now. 

On projects where an existing building is present, we try to maximise the value of existing façade materials by re-using (when technically feasible) or recycling in products of the same value, hence avoiding downcycling. For example, we are looking to reuse natural stone from buildings to be demolished on sites and reinstate this on the newly designed facades on multiple projects. We promote recycling existing glass and aluminium in close loop systems, liaising with the companies that can offer such services. Similarly, understanding the importance of recycled content in new aluminium and glass products, we are close to suppliers and sub-contractors to ensure that an onerous specification can still be delivered, with multiple procurement options in a competitive market.  

If we imagined the building as a material bank, the façade would probably be the most valuable asset because of its density and variety of materials in limited space. Cladding systems lend themselves very well to pre-fabrication, which allows a better-quality control, and there is a huge margin of improvement when it comes to design for easy disassembly. The key in the future will be to find ways to unlock the potential for the recovery of façade components and materials, thus retaining their intrinsic value by keeping them in use and give them a new life.