Sustainable retrofitting of Ireland’s existing building stock

Conor McGinn, Managing Director of sustainability building consultancy, SystemCore, discusses the importance of energy retrofits and asset rejuvenation. He details how an existing building can significantly reduce its embodied carbon emissions by reusing the existing structure and aligning with the principles of a circular economy.

I undertook my first sustainable retrofit in 2012 with the Pacific Centre redevelopment in Downtown Vancouver, a 640,000 sq ft mixed-use property. The building, which originally opened in 1973 with an ugly grey spandrelpanelled façade, was transformed into a LEED Gold (Leadership in Energy and Environmental Design) energy-efficient building with a modern glass façade.

The property owner decided to fully retain the existing structure instead of opting for a complete rebuild, which offered several advantages. This approach helped streamline the planning process, reduced construction time, and allowed the mall to remain operational, thereby minimising the loss of rental income. Additionally, the environmental benefits were significant – the new and improved fabric reduced thermal losses by approximately 40%.

The upgraded systems, which included daylight-adjusted lighting, dynamicallycontrolled ventilation and a connection to the city’s district heating system, made for high-efficiency energy on demand. These upgrades resulted in a total energy saving of 70% and a successful LEED Gold certification. This was a monumental success for a building that was 48 years old, placing it in the top 1% of efficient buildings in North America.

This project was ahead of its time and set a blueprint for many sustainable retrofit projects that I have completed since. While not all retrofits need to be stripped back to the structure, there is a certain pleasure in seeing a building transform so dramatically while also minimising environmental impacts.

In the 10 years since I worked in Vancouver, Irish developers have focused on new-builds, demolishing old buildings to make way for new

Retrofit is no walk in the park, however. There are challenges at every turn including fire compliance, structural integrity, budget constraints and live working environments. All of these add to the complexity and cost of upgrades.

Conor

McGinn, Managing Director of SystemCore.

energy-efficient structures with advanced fabrics and state-of-the-art systems. However, demolishing a building for a new one consumes significant energy in terms of embodied carbon, thus increasing its whole-life carbon.

A new building may be operationally efficient, but the savings must be weighed against the high embodied carbon cost of demolition and construction work, which includes emissions associated with the production, transportation and installation of building materials. Retrofitting an existing building can significantly reduce these embodied carbon emissions by reusing the existing structure and aligning with the principles of a circular economy.

Irish building regulations do not account for building life-cycle impact, waste management or material reuse, thus disincentivising developers from retrofitting. However, recent initiatives, including the Government-introduced Climate Retrofit Plan 2021, have started to turn the tide due to the introduction of grant funding.

SEAI grant supports for the retrofit of buildings are significant, with several options available depending on the scope of the project. These include Exceed, which supports up to 50% of CAPEX, SSRH up to 40% and CEG up to 30%. These grants are very effective at tipping the scale for investment decisions in terms of payback and will need to be continued and enhanced to ensure that Ireland meets its Climate Action Plan targets.

Retrofitting existing buildings is now becoming increasingly important as Governments and international bodies are setting stricter regulations and targets for carbon emissions. The combination of environmental, economic and regulatory factors is creating strong momentum for the sustainable retrofit industry, which is poised for significant growth.

The European Commission has stated that an investment of €1 trillion annually is required in Europe to achieve net zero carbon emissions by 2050. That equates to €14 billion annually for Ireland’s construction industry which would consume 40% of Ireland’s current construction output capabilities. Banks are preparing for a huge demand for capital deployment. AIB and BOI reported that their green lending was €3.7 billion and €3.8 billion respectively in 2023. This figure will need to increase significantly over the coming years.

Innovations in building materials and energy-efficient technologies are making retrofits more effective and affordable. The majority of existing buildings will still be in use by 2050, and therefore retrofitting them is essential to meet global climate goals.

Deep retrofits can reduce energy consumption and greenhouse gas emissions by 50-75%. These retrofits involve a complete upgrade of the building fabric, fenestration, lighting and mechanical systems. However, it is often cost-prohibitive to install a new fabric on an existing building, particularly if the building is less than 20 years old, when the payback period will likely exceed 25 years. Our recent studies have found that many commercial properties less than 25 years old can achieve a BER of A3 without altering the fabric.

Reducing fossil reliance

At SystemCore, our approach focuses on reducing reliance on fossil fuels by replacing systems with electricallypowered heat pump technology, introducing advanced dynamic control systems with sensor technology, and implementing local onsite renewable energy generation. We impose as little impact on the building as possible, re-using existing distribution systems where possible, avoiding costly builders’ works and loss of operational income.

Retrofit is no walk in the park, however. There are challenges at every turn – fire compliance, structural integrity, budget constraints, live working environments. These all add to the complexity and cost of upgrades. These challenges compound if not dealt with adequately.

A retrofit should start with creating a roadmap that lays out a pathway to success with clearly-outlined CAPEX requirements and results. This provides the information that allows stakeholders to clearly plan, phase and budget for the required initiatives, providing a clear target for success.