Dealing with a material world

First published in To Build magazine, November 2019

The materials used in the built environment are part of an evolving narrative. While enormous strides are being made in the area of green or sustainable building, humankind is also being made increasingly aware of the legacy that has been created by the casual neglect of our ancestors. In addition, we can’t draw a clear line between consumer-use materials and built-use materials. In most cases, they are one and the same.

′Plastic does not biodegrade. It simply gets broken down by mechanical current action into smaller or micro pieces, which enter the food chain.’

There is an understandable swing to looking at the contribution to a net zero impact of materials that are used in building projects. However, the concept of embodied energy and embodied carbon means that a sustainability assessment of a material depends on how wide you cast the assessment ‘net’.

For example, the use of fly ash and blast furnace slag in the manufacture of cement is gaining traction. However, the availability of these materials depends entirely on the combustion of coal for energy. So, the use of the by-products of combustion are mitigation measures, come with a load of embodied energy if traced back to its fossil-fuel-based source, and yet not final solutions in themselves. The same goes for many recycled materials, e.g. ecobricks are being packed with single-use plastic bags and other waste. If you remove the source of the waste you will, as a consequence, no longer have access to the recycled material over the longer term. (In defence of ecobrick warriors, of course, the sequestration of all plastic waste in this manner will take a very long time, hence presenting an amazing resource available to the building trade).

Ultimately, we need a return to natural substitutes for waste forming materials or scrap them completely. For example, the use of bioplastic as opposed to its synthetic versions could rid the atmosphere of 4.3 gigatons of CO2 by the year 2050 [Ref: www.drawdown.org].  Bioplastic usage, which curiously first emerged in early model Ford cars, was sidelined (or more accurately, blindsided) by the wealthy and influential oil industry in the USA during the mid-20th Century. 

Careful with mixing

The experts add a caveat, however. Bioplastic recycling is a process that needs to take place independently from oil-based plastic recycling, and above all, plastic from both sources should never be mixed in the same product because this prevents all future recycling of both, leaving incineration as the only remaining option to landfill.

The single largest and most harmful contribution to global warming on the planet comes from one material: refrigerant gas. Hence, the switch to other kinds of refrigerant gas and better management of the materials could result in 89.74 gigatons of CO2 being removed from the atmosphere by 2050.

The danger of business as usual

The impact of a business as usual approach in the built environment and consumer spaces is well documented. The notion of “take, make, waste” which represents the business as usual approach, has resulted in most of the omnipresent environmental problems of today. This cannot continue if humankind is to survive the current century.

The plastic ocean

One of the keynote speakers at the 2019 Green Building Convention was Jo Ruxton, an award-winning film producer and plastic pollution campaigner. Her organisation, Plastic Ocean, has relentlessly pursued the facts about exactly how much plastic has ended up in our oceans, exactly where it is being amassed and what is happening to it.

‘In my lifetime, plastic production has increased by 3 900% per year. Last year, it totalled 315 million tons, 8 million of which were deposited in the sea,’ she says. Supporting this observation, the Drawdown team states that one-third of all plastics end up in ecosystems, while only 8% is recycled on a global basis.

Ruxton has in her lifetime, dived deeper into the sub-aquatic world than most and witnessed its gradual devastation first-hand. According to what she has seen and counted, 90% of ocean waste lies at the bottom. It was while filming “Blue Planet” in the 90s, that Ruxton first felt compelled to act. Her film, “Plastic Ocean – We Need a Wave of Change”, has been a chilling success in exposing the situation as it now stands.

In Ruxton’s opinion, which is shared by leading scientists and backed by hard observations, plastic does not biodegrade. It simply gets broken down by mechanical current action into smaller or micro pieces, which are now entering the food chain. 

The result of this pollution of our seas is now well documented and is resulting in the extinction of multiple species which co-habit the Earth with humans. 

Apart from this looming environmental tragedy of extinction, humankind’s existence is also threatened, as vital links in the food chain are broken. For example, it is predicted that the consumption of surviving fish stocks could become deadly to humans, due to the increase of plastic waste and toxins in the tissues of the fish. In some cases, certain plastics, due to their molecular nature, are being absorbed into chains of fatty acids and are now mimicking food.

Within the building materials category, it is universally recognised that any step in the direction of reducing and re-using existing waste stockpiles, is a huge step in the right direction.