The Future Of Sustainable Building – Costing The Earth

Building a sustainable future is more than just recycling and building with eco-friendly materials. Although those elements are key components, there’s more to consider than perhaps first meets the eye.

Following the pandemic, many people have now adopted a more flexible approach to work. Hybrid working from home and the office, and in some cases working from home entirely. This has led to a growing number of offices and retail outlets standing empty, particularly in city centres where the morning commute is less than desirable.

Leaving buildings empty often leads to neglect. Becoming tired in appearance, paint peeling, windows boarded. It begs the question – what do we do with these buildings that are now considered to be redundant?

Faced with two options, developers may choose to knock them down; Start again, writing off the loss of materials and energy involved in their construction and demolition. Or, the far more sustainable approach, would be to find a way to reuse these buildings, redesign and refurbish them to meet our modern-day ideals.

How environmentally damaging is the construction industry?

Almost half of the total global CO2 is a product of the construction industry, estimated at around 40%. RIBA President, Simon Alford, has broken this down further revealing a third of that pertains to the construction of new buildings – bricks, timber, concrete, and steel that come together to make the building. In addition to the vehicles that transport these materials.

Another third is in operation energy, currently gas and electric. The final third is thought to be in the maintenance, repair, and reconstruction of a building throughout its lifetime.

How big an issue is the demolition of perfectly good structures?

By the figures above, it is clear that if we were to avoid the demolition and rebuilding of all structures entirely, a third of all CO2 emissions related to construction could be avoided. Although not all buildings can be saved, this demonstrates the scale and importance of retrofitting and renovating existing buildings.

If the demolition and reconstruction of buildings have such a negative impact, why do we continue to do it?

Over the last 50 years, we are a blip in history. If you admire many historical buildings you’ll see that they are amalgams from different times. Behind a Georgian building, you may find an Elizabethan home; A reinvention of an existing structure to keep it up-to-date with ever-changing lifestyles.

The current pattern of demolition and rebuild was following a 20th-century shock from cultural and art movements that rejected industrialisation, built on aspirations of creating a brave new world. Across Europe, there was the added motive to rebuild this new world. Following the destruction and decimation of the built environment after two world wars, and one of the largest migrations of people that we have seen in recent history, communities had to be rebuilt through necessity.

But it is only now, that as a generation we are rediscovering something that had always been a part of architectural history. Retrofit.

How does outdated legislation impact current construction projects?

Outdated legislation regarding construction can lead to more harm than good, an example of this can be seen in the Capital itself. The project ‘One Museum Street’, perfectly surmises the entire debate that surrounds retrofit vs building anew. The current building has been largely vacant for over 3 years, with 95% of the building remaining unused due to neglect.

The developers for this project are seeking to knock down the existing building – Selkirk house. It is a classic commercial development, built in the 1960s from a precast concrete frame that towers 16 stories high. Structurally, the developers and architects confirmed that the building is in sound condition, so there is potential to convert. However, the floor to ceiling height is not suitable for their intentions for it to be used as high-end offices. They are hoping to rebuild a new development in its place that scales 2 thirds taller than the current building.

However, following the shift in work patterns, it is considered that there is an ever-declining demand for office spaces in general. Never mind high-spec offices. So, throughout demolition and rebuild, the expense to the environment, is there any likelihood that the new building will be utilised to its full potential as office spaces?

An organised group named ‘Save Museum Street’ are fighting to prevent the demolition and support a retrofit instead. Suggesting that the space would be better used as in-demand housing, or workshops to support the surrounding theatres. They argue that the impact of the demolition and rebuild of this project alone is estimated to release around 64,000 tons of CO2 over 60 years.

As a representation, this is over a million trees cut down, or a total area of woodland the size of Epping Forest destroyed to build a single office space in London.

However, the developers are building within the current environmental restrictions and can evidence metrics and measurements that demonstrate the project’s compliance with the legislation. Whilst the developers may be meeting these requirements, the argument is that what is considered ‘green building’ under the current legislation, is still vastly more harmful than retrofitting the existing building if the existing building is structurally sound. One of the issues with the outdated legislation is an understanding of recycling.

How can recycling be wrong?

Whilst all recycling usually comes from good intentions, often the process of reusing existing materials can quickly become downcycling. For example, when it comes to reusing existing materials, such as bricks, they aren’t being recycled back to the same level they were originally used for. Instead, they may be crushed and used as a base for a motorway.

To recycle in any meaningful way, and ensure that the time and energy originally invested is put to proper use, the materials need to be used at the highest possible level, rather than the lowest option.

What is the future of Sustainable Building?

Sustainable building is not solely about picking old buildings, but rather how we use the built and natural environment around us, and how architects begin to think differently with sustainability as an important factor in their design. An example of this can be found in Southwark, London. On a net-zero carbon project designed by Bennetts Associates.

An old 1950s printworks, full of character with a raw concrete frame, sturdy brickwork, and petite steel-framed windows is undergoing a modern reinvention. A few years ago, any other developer would have likely demolished due to the outdated aesthetic. But the cost to the environment would have been astronomical, and one of the reasons why this team of architects chose to instead, save it.

The existing framework of the build is robust enough to allow the developers to build on top of it with steel and cross-laminated timber. Unlike a lot of construction materials, before the wood is used in building it will have soaked CO2 from the atmosphere. So, rather than producing carbon over its lifespan, it has already locked it into the building, helping to bring down emissions by starting from a carbon-negative position. In addition, the number of vehicles required to remove demolished materials and deliver new materials can be more than halved by simply working with the existing building.

Learning the lessons of climate change and applying them to shape the future of architecture

The future of sustainable building can often be far more complex than simply CO2 emissions and profit. Quite often another factor that is rarely discussed in the construction industry, and something we are all guilty of, is relating to our egos.

Smith Mordak an Architect at Buro Happold and a member of Architects Declare, explains that some of the problems can be down to how architects have been educated and socialised. Stating, “We have a solution bias to a building being a solution to a problem.” But, a lack of space or an unfavourable layout is not always resolved by building something new. Referencing a project that she had previously worked on for a hospital Mordak explains “We deeply analysed the way the hospital was operating”. Later revealing to her clients that “Actually you don’t need an extension, you don’t need to spend that money or carbon. You just need to reconfigure your existing spaces to achieve what you need to achieve.”

Although Smith Mordak admits that it would have been an exciting opportunity to redesign the extension to the hospital. “We have to step back and think hang on a minute; is this thing I’ve been dreaming about since I was 6 the right answer? Or is it something else?”

“…that’s a really difficult cultural thing for an architect.”

So how do we move away from that culture?

Although we see more and more celebrated buildings shifting in favour of refurbs, Mordak believes that this does not tackle the more pressing issue.

“I think actually should we be thinking of architecture as this heroic sexy answer to a problem? Is that the root of the problem?”

She criticises the order in which architects and developers approach a project. First by assessing the site, developing a brilliant idea and then bringing together the materials to realise that dream. Stating “That’s backwards. First, we [should] look at the site, and have deep audits. Then, what do we have available on the site? How can we reuse things in the area? Which manufacturers and suppliers work with upcycling? And how can we create a design that reconfigures those resources? It’s a reverse design process that our industry is not set up for.”

(Right) A Westbury Orangery from 2021
The same timeless design, in a modern setting

(Left) A Westbury Orangery from 1999

Timeless in style and construction

Is there a demand for sustainable building?

The emergence of net-zero-carbon commercial targets has become important to consumers and corporations. Particularly service-based businesses where often the biggest contributors to carbon will be any buildings and business travel. By utilising sustainable building spaces, they can remove a large portion of carbon from their corporate profiles.

The other factor to consider is its character. People are increasingly gravitating more towards older buildings, even those that are rough and industrial. The demand for these buildings has also begun to raise their market rental value, as everyone seeks more one-of-a-kind spaces.

To hear more about these issues in more detail, a radio 4 episode of ‘Costing the Earth’ by Architect Elsie Owusu explores some of how architects, developers and property owners may be contributing to unstainable buildings, and how outdated understandings of sustainability can be quite misleading to anyone embarking on a project of their own.