Green retrofit - well, its’s quite the buzzword in the development industry at the moment, but what is it really?
It can actually be defined as a number of things, but in reality it is ‘exactly what it says on the tin’ - green retrofit is the sustainable refurbishment of an existing building to make it more efficient, better for the environment and sustainable for the future. It includes either major or minor refurbishment as well as the installation of products in an attempt to reduce the carbon footprint of the building and its future operations.
There is no set criteria as to what does and doesn’t constitute green retrofitting, as this is obviously dependent upon a number of factors such as the make-up of the building, the challenges presented by this and the deliverables of the project. In planning a green retrofit or refurbishment, there are however four key considerations to keep in mind:
- What are the current and future uses of the building? And will this change over time?
- What cost effective technologies and products are available to help achieve deliverables?
- Will an isolated or holistic strategy be required?
- Do the proposed strategies work in unison or compete against one another?
Types of retrofits
Painting on a blank canvas is obviously the preferred development strategy because it has traditionally been cheaper, presents fewer challenges in design and does not come with inherent potential design and workmanship issues that may need to be overcome. In most cases, achieving a desired standard will be easier and better value on a new build than on a refurbishment or retrofit. It is these challenges, together with the refurbishment costs, that predominately deter developers and owners from proceeding with green refurbishments.
Consideration should be given to the fact that green retrofit can consist of smaller projects and does not necessarily require a complete refurbishment of an existing building. This is not a new concept, but one that has been around for decades – it’s just now that it is being implemented on a much larger scale. An early example includes the conversion of lighting systems from aluminium to LED. Today, there are a variety of other measures and strategies being implemented including the installation of solar panels, ground source heating, green walls and roofs, smart meters, heat disbursement and water efficient taps.
Prominent asset owners are starting to look at green retrofitting in order to upgrade their property portfolio as a means to distinguish themselves from their competitors and ensure greater returns over the longer term.
One Triston Square
Recently, British Land undertook a significant analysis of its building One Triston Square in London in order to help improve the building’s overall efficiency (and bring it into the modern age).
Sustainability and efficiency were of course the primary targets of the project but equally important were the ever changing needs of its tenants; in particular, the way in which they worked and their focus on sustainability. Designed and built in the 1990s, the building was somewhat dated and needed to be repurposed to facilitate these needs.
The project involved the construction of three additional floors together with the refurbishment of the existing building. In delivering this project, the client was focused on sustainability throughout. This meant that not only was there simply a focus on improving the building’s operational efficiency going forward, but also a fundamental delivery methodology focused purely on sustainability from project inception through to procurement, construction and operations.
In adopting this holistic approach to sustainability, the project achieved the following outcomes:
- 56% embodied carbon saving;
- 43% operational saving (forecasted) by upgrading building systems and functionality;
- 66% cost saving on the circular façade by refurbishing the existing façade using a pop-up factory nearby; and
- a new visionary methodology for the client’s (and its partners’) asset programs. 
Empire State Building
Another iconic building which has undergone a major green retrofit is the Empire State Building in New York.
The purpose of this project was to reduce the building’s carbon footprint, and in particular its carbon dioxide emissions, in order to align with modern and future building standards. In upgrading a building almost a hundred years old, ensuring cost effectiveness was no easy feat - but after having originally identified over sixty potential efficiency programs, the program was reduced to eight project streams which included the following delivery packages:
- remanufacturing existing insulated glass with double-glazed windows;
- installing over 6000 insulated reflective barriers behind radiators;
- reducing lighting power density in tenant spaces (automatic light dimming);
- chiller plant upgrades;
- installing variable air-conditioning units;
- upgrading the building control system;
- the introduction of a demand control ventilation system (allowing for outside air temperature to be introduced rather than having to cool air); and
- improving tenant energy management, including smart metering for tenants.
The primary reason these eight packages were chosen was because when combined, they achieved far greater gains than those of other packages in isolation and therefore were the most cost effective solution. The end result saw a decrease in the building’s carbon dioxide output by almost 38%.
Incentives to drive change?
Commentators suggest that over 80% of the 2050 building stock is already in existence. Inevitably, if the UK is going to achieve net carbon zero by 2050, this existing stock will need to be improved and a large proportion will need to be adapted by way of retrofit and refurbishment.
It will be interesting to see how sustainability and carbon dioxide reduction will become another key deliverable, equal to costs and risks. Presumably, this will be achieved through carbon taxing schemes or other mechanisms introduced via the Government’s net zero strategy.
Cost effective technology and sustainable products are the catalysts for success, yet presently these are the major hurdles to overcome when presented with this type of project. Common complaints of developers and builders alike is that green solutions create more problems than answers, especially in the context of price and adaptability.
Of course, technology will evolve over time and become cheaper and more applicable to building and retrofitting needs but currently there simply isn’t enough appetite in the market to drive the change that is needed. Incentives need to be made available to developers and contractors if significant developments are going to be made in the area of green retrofit going forwards, especially as the industry has shown limited enthusiasm for change to date.
Boris Johnson has now published his ten point plan for a Green Industrial Revolution. This includes his aim of “making our homes, schools and hospitals greener, warmer and more energy efficient” and it is clear that green retrofit will have significant government support. With that in mind, it is obvious that although there are a variety of problems associated with the green retrofit model as is currently stands, this does not mean that small retrofit projects cannot be undertaken now in order to get the ball rolling as a means of achieving net zero by 2050.