The greenest buildings are ones that already exist24 February 2023

Fergal White

Fergal White Senior Associate

One of the principal ways identified for achieving the Paris Agreement’s long-term goal of limiting global warming to below 2°C (compared to pre-industrial levels) is decarbonisation - essentially a combination of measures by which a carbon footprint can be reduced.
In simpler terms, decarbonisation is essentially consuming and wasting less. When it comes to buildings, this means optimising energy efficiency, particularly when it comes to how we heat and cool them. That being said, decarbonisation is not just about bringing down energy bills.

Reducing the ecological impact of buildings down to what it costs to service them can make a strong environmental case for new construction. However, since the 1980s, with the ongoing improvement of the building envelope in terms of air tightness and insulation values, the vast majority of carbon dioxide released associated with a new building is now “embodied carbon” as opposed to carbon released as part of the servicing of the building. So once we consider the impact of construction itself, the argument for preservation of existing real estate becomes more robust, especially when we consider the impact caused by the manufacturing and transportation of concrete, steel, cement windows and other building materials.

Retrofit is where we must begin our decarbonisation journey

Buildings, in how they are currently operated and constructed, account for the largest share (39%) of global energy-related carbon emissions, with operations emissions accounting for 28%. Globally, it is estimated that 80% of the homes that people will inhabit in 2050 are already built, while up to 75% of today’s buildings will still be in use at the halfway point of this century. Meanwhile, right here in Ireland, nearly half of homes have a BER of D1 or lower.

Retrofitting is the act of fitting new systems designed for high energy efficiency and low energy consumption to buildings previously built without them. One key element, according to CAP21 (Ireland’s Climate Action Plan 2021), to decarbonising the building sector is the delivery of the equivalent of 500,000 homes retrofitted to a BER of B2/cost optimal or carbon equivalent, and the installation of 400,000 heat pumps in existing Irish business premises by the end of 2030. It is estimated that improving the energy efficiency of the non-residential sector by 20% and increasing the proportion of renewable electricity in the grid to 80% would achieve the Irish government’s 2030 decarbonisation target of 51% for the non-residential sector.

The benefits of a retrofit strategy

Decarbonising an existing building can start with a step as simple as fitting energy-efficient light bulbs to installing solar panels, smart meters and state-of-the-art sustainable water and heating systems. The goals in any retrofit strategy, whatever its level of complexity, will be to increase the building’s energy efficiency, make it cheaper to run, and have a lower impact on the environment.

The benefits of retrofit-enabled decarbonisation are that it creates sustainable jobs, improves health and wellbeing, and can increase the value of the property, all of which might also be considered goals in themselves.

How MCA reimagines and remodels existing buildings

Of course, retrofitting an existing building does not have to be concerned only with updating its internal systems and fittings. Projects that MCA has completed, such as Eaton House and No.1 Cumberland Place, have seen our team succeed in remodelling office buildings from the 1960s and 1970s with contemporary external façades and features that preserve the aesthetic of the area, slotting comfortably into the surrounding architectural landscape and period buildings. Meanwhile, renovation projects such as Dockline are examples of how the challenges of remodelling a dated office block present opportunities to create unique buildings with character and presence.

The challenges of a retrofit inspire innovation

The Dawson-Nassau-Molesworth Street quarter of Dublin 2 has been rejuvenated by urban renewal in the last decade. For some of the projects involved, retrofit provided the solution. When IPUT approached the team at MCA to develop 40 Molesworth Street, there was the option of complete demolition. However, we embraced reusing the existing building and the opportunities the original structure offered. Repurposing a building from the 1960s brought numerous challenges; introducing a contemporary airtight façade into a structure with very little construction tolerance and consisting of handmade brick, to name just one. However, with the use of an efficient VRV air conditioning system, LED lighting that responds in real time to external lighting conditions, and an air tightness of less than 3 m³/m²/h, the LEED (Leadership in Energy and Environmental Design) Gold standard was achieved.

If you're considering the repurposing or reimagining of an existing building, why not get in touch with the team at MCA? We’d love to hear from you.

Mitigation Pathways Compatible with 1.5°C in the Context of Sustainable Development
Bringing embodied carbon upfront
Property Week Climate Crisis Challenge Podcast
Decarbonising our built environment - Reflecting on the Climate Action Plan (KPMG)
Climate Action Plan 2021 - Securing Our Future
National Retrofit Plan

Fergal White

Fergal White Senior Associate