We think sustainable urban planning is new – but the ancient Romans were recycling buildings millennia ago

“Hmm, we can reuse this.” The Colosseum. Image: Getty.

In any debate on new construction in our urban centres you are likely to hear phrases like sustainable urban planning, adaptive reuse and recycling heritage – so much so that anyone would be forgiven for thinking that these were modern concerns.

However, these principles have a long history in the ancient world. Anywhere permanent materials such as marble and granite were used to build monuments and infrastructure, recycling and reuse followed.

The ancient Roman world is littered with examples of architectural recycling. Under the banner spolia studies, archaeologists and art historians have increasingly focused attention on the hows and whys of reuse in antiquity.

Ancient architectural recycling falls into two broad categories: adaptive reuse of immovable structures, when a building or monument is renovated and its primary function changes; and reuse of architectural elements, where both functional and decorative material is removed from one building to be incorporated in another (spolia).

While this is often associated with changes in ideologies, there is also evidence of opportunistic recycling following disasters. These events created a surplus of materials that could be salvaged for new constructions.

Same aesthetic, new function

In the hearts of Rome and Istanbul, the capitals of the ancient Roman and Byzantine empires, stand the Pantheon and Hagia Sophia. These iconic and celebrated public buildings were adapted for different religious purposes throughout history. Both maintained their heritage aesthetic, while renovating their function.

The Pantheon was adapted from a pagan temple to a consecrated church in 609CE. The exterior Pantheon was largely unchanged, while the interior was stripped of its pagan elements.

Hagia Sophia was adapted from a Christian basilica to an Islamic mosque following the fall of Constantinople to the Ottomans. The exterior required only the addition of minarets. The interior was whitewashed to cover the rich mosaics of its previous life.

Civic buildings, too, were prime candidates for adaptive reuse, thanks to the rich materials and design of their original constructions.

The restored Library of Celsus, Ephesus, with excavated ancient water pipes in the foreground. Image: author provided.

At the newly listed UNESCO World Heritage site of Ephesus, the tourists’ visit culminates at the impressive multistorey Library of Celsus. Originally built in the second century, an earthquake and fire destroyed the library and its holdings in 262CE.

The impressive facade of the library was salvaged and adapted 100 years later into a nymphaeum, a public water fountain. The adaptive process incorporated other recycled materials from nearby public monuments, mostly marble blocks and free-standing sculpture, fitting the change in function. This reuse gave the non-functional, but already historic, structure a new life.

Recycling as propaganda

The Arch of Constantine is possibly the most referenced structure in spolia studies. Dedicated in 315, the arch celebrates Constantine’s victory over his rival Emperor Maxentius at the Battle of Milvian Bridge.

The Arch of Constantine, where recycling even serves the purpose of propaganda. Image: Steve Kershaw/creative commons.

First noticed by Raphael, the arch was built from a mixture of new and recycled decorative building material. Scenes of animal hunts, religious sacrifice and historic battles were taken from monuments built in the second century CE, including those of the emperors Hadrian, Trajan and Marcus Aurelius. These scenes represented the “golden years” of Rome’s past.

Constantine didn’t just simply recycle these pieces; he reworked the stone faces of Rome’s greatest emperors into his own image. With this act, the emperor takes on all the great qualities of his predecessors and sets himself up as the rightful leader of Rome. This recycling takes us into a world of political propaganda, something the Romans were renowned for.

This bold inclusion of old material in a new monument for Rome led to a whole new recycling trend in architecture. Decorative elements such as columns, capitals and architraves were given new life in buildings of the fourth century CE.

The trend became so popular that new laws were created to protect public buildings from being stripped of their decoration. Only if a building could not be restored was it permitted to recycle that building’s materials.

Opportunistic recycling

Natural disasters and invading armies often left ancient monuments in ruin. These created a stock of marble, granite and sandstone that could be reused in new constructions.

The theatre at Nea Paphos, the scene of archaeological excavations since 1995. Image: Paphos Theatre Archaeological Project, University of Sydney/author provided.

In Nea Paphos, Cyprus, a devastating earthquake destroyed the 8,500-seat theatre in 365CE. Instead of being rebuilt, the theatre became a useful source of marble and stone. Many of the columns and decorative architecture were carried off to be reused in the new Chrysopolitissa basilica, 300 metres down the road.

In Athens, a late Roman fortification wall is a hodgepodge of recycled materials. Image: F. Tronchin/Flickr/creative commons.

In Athens, the invading Heruli destroyed several public buildings in 267-8 CE. However, this left behind a good supply of reusable materials. The Athenians recycled many elements, from column drums to relief sculpture, in a large fortification wall circling the heart of the city. Today, the wall appears as a hodgepodge of recycled elements from Athens’ classical past.

In 2004, the Australian Department of the Environment and Energy released a document supporting adaptive reuse. This booklet said:

Historic buildings give us a glimpse of our past and lend character to our communities as well as serving practical purposes now.

In 2011, the renamed department released a guide to help realise new recycling opportunities related to construction and demolition. These principles are part of our general thinking about urban planning. However, it is clear that this is not a new approach to sustainable urban development. Rather, it continues an ancient tradition of recycling.The Conversation

Candace Richards is acting senior curator at the Nicholson Museum, University of Sydney.

This article was originally published on The Conversation. Read the original article.


 

 
 
 
 

Green roofs improve cities – so why don’t all buildings have them?

The green roof at the Kennedy Centre, Washington DC. Image: Getty.

Rooftops covered with grass, vegetable gardens and lush foliage are now a common sight in many cities around the world. More and more private companies and city authorities are investing in green roofs, drawn to their wide-ranging benefits which include savings on energy costs, mitigating the risk from floods, creating habitats for urban wildlife, tackling air pollution and urban heat and even producing food.

A recent report in the UK suggested that the green roof market there is expanding at a rate of 17 per cent each year. The world’s largest rooftop farm will open in Paris in 2020, superseding similar schemes in New York City and Chicago. Stuttgart, in Germany, is thought of as “the green roof capital of Europe”, while Singapore is even installing green roofs on buses.

These increasingly radical urban designs can help cities adapt to the monumental challenges they face, such as access to resources and a lack of green space due to development. But buy-in from city authorities, businesses and other institutions is crucial to ensuring their success – as is research investigating different options to suit the variety of rooftop spaces found in cities.

A growing trend

The UK is relatively new to developing green roofs, and governments and institutions are playing a major role in spreading the practice. London is home to much of the UK’s green roof market, mainly due to forward-thinking policies such as the 2008 London Plan, which paved the way to more than double the area of green roofs in the capital.

Although London has led the way, there are now “living labs” at the Universities of Sheffield and Salford which are helping to establish the precedent elsewhere. The IGNITION project – led by the Greater Manchester Combined Authority – involves the development of a living lab at the University of Salford, with the aim of uncovering ways to convince developers and investors to adopt green roofs.

Ongoing research is showcasing how green roofs can integrate with living walls and sustainable drainage systems on the ground, such as street trees, to better manage water and make the built environment more sustainable.

Research is also demonstrating the social value of green roofs. Doctors are increasingly prescribing time spent gardening outdoors for patients dealiong with anxiety and depression. And research has found that access to even the most basic green spaces can provide a better quality of life for dementia sufferers and help prevent obesity.

An edible roof at Fenway Park, stadium of the Boston Red Sox. Image: Michael Hardman/author provided.

In North America, green roofs have become mainstream, with a wide array of expansive, accessible and food-producing roofs installed in buildings. Again, city leaders and authorities have helped push the movement forward – only recently, San Francisco created a policy requiring new buildings to have green roofs. Toronto has policies dating from the 1990s, encouraging the development of urban farms on rooftops.

These countries also benefit from having newer buildings, which make it easier to install green roofs. Being able to store and distribute water right across the rooftop is crucial to maintaining the plants on any green roof – especially on “edible roofs” which farm fruit and vegetables. And it’s much easier to create this capacity in newer buildings, which can typically hold greater weight, than retro-fit old ones. Having a stronger roof also makes it easier to grow a greater variety of plants, since the soil can be deeper.


The new normal?

For green roofs to become the norm for new developments, there needs to be buy-in from public authorities and private actors. Those responsible for maintaining buildings may have to acquire new skills, such as landscaping, and in some cases volunteers may be needed to help out. Other considerations include installing drainage paths, meeting health and safety requirements and perhaps allowing access for the public, as well as planning restrictions and disruption from regular ativities in and around the buildings during installation.

To convince investors and developers that installing green roofs is worthwhile, economic arguments are still the most important. The term “natural capital” has been developed to explain the economic value of nature; for example, measuring the money saved by installing natural solutions to protect against flood damage, adapt to climate change or help people lead healthier and happier lives.

As the expertise about green roofs grows, official standards have been developed to ensure that they are designed, built and maintained properly, and function well. Improvements in the science and technology underpinning green roof development have also led to new variations on the concept.

For example, “blue roofs” increase the capacity of buildings to hold water over longer periods of time, rather than drain away quickly – crucial in times of heavier rainfall. There are also combinations of green roofs with solar panels, and “brown roofs” which are wilder in nature and maximise biodiversity.

If the trend continues, it could create new jobs and a more vibrant and sustainable local food economy – alongside many other benefits. There are still barriers to overcome, but the evidence so far indicates that green roofs have the potential to transform cities and help them function sustainably long into the future. The success stories need to be studied and replicated elsewhere, to make green, blue, brown and food-producing roofs the norm in cities around the world.

Michael Hardman, Senior Lecturer in Urban Geography, University of Salford and Nick Davies, Research Fellow, University of Salford.

This article is republished from The Conversation under a Creative Commons license. Read the original article.