Our third Healthy Buildings Conference and Expo took place on Thursday 28th February 2019 at London South Bank University. The theme was ‘Plastics in Construction: Issues, Impacts and Alternatives’ and two leading sustainability journalists have written summary write-ups of the conference sessions.
A summary article written by Hattie Hartman, Sustainability editor, Architects’ Journal. First published on 21st March 2019.
If you attended Plastics in Construction, the ASPB’s third annual conference last month, you’ll probably make a concerted effort never to touch single-use plastic again. The message that came across from the sell-out event at London South Bank University is that avoiding, or at least reducing, the use of plastics in construction is challenging, but essential.
Keynote speaker Emily Penn, an architecture graduate from Cambridge, took a life-changing decision in 2008 when she decided to take her year out in Melbourne, Australia. Hitching a ride on a bio-diesel fueled boat, she was shocked when she dove into the ocean ‘a thousand miles from anywhere’ and found herself in sea of plastic. This jump-started Penn’s unexpected career as an ‘ocean advocate’, campaigning for the reduction of plastics and toxins in the ocean. Penn founded and heads eXXpedition, a not-for-profit which organizes all-women sailing expeditions around the world to study ocean pollution.
Penn’s research revealed the dire knock-on effects of climate change on plastic pollution. Locals struggle to catch fish due to overfishing and struggle to grow crops due to salty soils resulting from sea level rise. These remote destinations resort to the quick-fix solution of imported food, often in plastic containers, but are ill-equipped in terms of landfill, so that plastics, many designed to last forever, end up in the ocean.
This experience prompted Penn to organise an expedition in search of the infamous islands of plastic (the size of Texas or France) often reported in the media. What she found is that these floating islands of plastic are a myth: plastic does indeed float in patches, but the bulk of the 8 million tonnes of plastic dumped into the ocean annually fragment into tiny pieces, smaller than a little fingernail. These pellet-like bits of plastic do not biodegrade; some sink to the ocean bottom and are almost impossible to clean up.
Penn explains that only about 9% of plastic used globally is currently recycled. Easiest to recycle are items made from one type of plastic, but items such as toothbrushes, and many construction products, contain more than one type of plastic, which makes them very difficult to recycle. Penn says this mismatch between product design and material science must be rectified to maximise the possibility of recycling and reuse.
Penn and her colleagues used special sieves to collect microplastics in order to study their chemical composition and try to identify their source. They also attach sensors to track the debris. A further unintended consequence of the explosion in marine plastic is that fish mistake microplastics for food.
Emily underwent a blood test and found that 29 of 35 chemicals banned by the United Nations showed up in her bloodstream. “While the environmental challenge of plastics in the ocean may seem remote, we all already have a chemical footprint which directly affects our endocrine system,’ explains Penn. This led her to recruit all-women crews for her expeditions: journalists, artists, product designers, teachers, marine biologists, chemists, policy makers.
Penn notes that there is no silver bullet to solve the plastic crisis, but her mantra now is AIR: Avoid, Intercept, Redesign. She cites the success of the Adidas Parley line which recycles plastic bottles into trainers and tenniswear, but notes that the trainers themselves will eventually end up in landfill.
Products, and this goes for building products too, need to be completely redesigned so that they are biodegradable and don’t become waste. Currently there is a disconnect between material science and product design. Every sector of society needs to change, so that disposable plastic goes the way of smoking. When it comes to the built environment, Penn advocates more modest buildings which are fit for purpose and celebrate nature. Campaigning to raise awareness is essential to effect regulatory change because the construction sector is ‘policy dependent’ and slow to change.
Innovators in industry who have greater resources for R&D must lead the way, along with consumers who can deploy ‘social power’ to mobilise from the bottom up. Penn’s next expedition, set to depart from Plymouth in October 2019, received applications from 10,000 women across the globe.
A rapid-fire 90-second exhibitor showcase followed Penn’s keynote, an effective platform for suppliers to briefly promote their products. Several suppliers highlighted their journey to reduced plastic use with a particular focus on packaging.
Professor Sean Smith of Edinburgh Napier University described the cluster of research groups, which operate under the umbrella of the university’s Institute for Sustainable Construction, ranging from timber to energy, smart cities, transport and engineering. He then discussed the challenges arising from the increased use of plastics in construction over the last three decades, largely driven by the push for energy efficiency and increased use of materials with lower U-values such as rigid foam. Smith highlighted the increased use of offsite manufacturing as a way to reduce waste and facilitate recycling and ‘take-back’ schemes. Early signs of circular thinking are apparent in products such as Accoya Wood and innovations in fire-proofing structural timber enable taller timber buildings. Smith noted that Scotland supplies 70% of UK timber.
In terms of plastics, a report published by ZeroWasteScotland in 2015, Plastics Evidence: Evidence base for Plastics Recycling in Scotland summarizes data on plastic waste streams north of the border. Project Beacon is an innovative facility near Perth which uses an integrative approach of mechanical and chemical recycling to target difficult plastics such as PVC piping and gutters and aims for a 90% recycling rate. The university has also been involved in R&D exploring the potential of using recycled plastics and foam in new construction in applications such as acoustic floors. Smith noted that in some cases products which include plastic may perform better under LCA if they can be deconstructed and reused at the end of life.
Surprisingly, Scotland’s 2020 Climate Group identified the packaging of white goods for new homes and the packaging of construction products as the major source of plastic in construction waste streams, not the products themselves. Smith cited cardboard packaging by manufacturers such as Encase or the French company L’Hexagone as alternatives. Professor Smith then turned to the global challenges facing the construction industry, estimating that $100 trillion will be spent on buildings, transport and infrastructure in the next two decades, representing 15% of global GDP. Almost 60% of that growth will take place in China, India and the US, with India growing twice as fast as China and overtaking China’s population by 2022.
The global demand for housing in the next 80 years will be 6.25 times the European Union’s 320 million homes created over the last 5 centuries. The challenge is further exacerbated by the fact that 2.4 billion people who live in low elevation coastal zones (LECZ) subject to storm surge. High risk areas need to be redesigned to avoid the recurrence of events like Hurricane Sandy and Fukushima. According to Smith, the UN and other international agencies must take a global view and be ready with a resilient plan rather than responding reactively. This means designing sustainable communities, including pre-fabricated units which can be deployed globally in emergencies, using local and natural materials where possible and designing for deconstruction.
Dr. Stephanie Wright, a researcher in King’s College’s Medical Research Council Toxicology Unit, concluded the morning with a disturbing presentation entitled ‘A Plastic World’ which focused on the health impacts of microplastics. Microplastics of less than 1mm in size are ubiquitous, and upwards of 80% come from synthetic fibres. They are ingested by a wide range of species, particularly shellfish. We also ingest microplastics through sea salt, bottled water and household dust. The air we breathe is increasingly being recognised as another potential source of exposure to microplastics.
To date, dietary and airborne exposure to microplastics is understudied so the health impacts are not conclusive. It is clear that prolonged exposure to high concentrations causes occupational lung disease. With the escalating use of plastic, greater attention to how it is disposed of is essential in order to avoid a major health crisis.
Presentation of the first annual ASBP Awards concluded the morning session. The awards are judged according to six pillars of transparency: health and well-being, resource efficiency, whole life carbon, ethics and transparency, technical performance and social value. Each project was presented by the designer, followed by an audience vote.
Chosen by both the judges and the conference audience as the winner, Arboreal Architecture’s Bowman’s Lea is a DIY retrofit by architect Harry Paticas of his own home, a 1978 terrace house in Lewisham. Engagingly communicated in an exploded hand-drawn diagram, the architect’s step-by-step process pushed the boundaries on resource efficiency, using offcuts of cork insulation to insulate a second room, and engaging with suppliers about take-back schemes for surplus materials. To date, the refurbishment, which is ongoing, has reduced space heating demand by more than 50%, with an ultimate target of 90% once all internal wall insulation, new windows and a garage door are in place.
The project is also notable for the architect’s extensive knowledge-sharing, through Passivhaus Open Days, leafleting to neighbours and running workshops with local school children.
A summary article written by Kate de Selincourt, freelance journalist and regular contributor to Passivhaus Plus magazine.
The ASBP’s 2019 Healthy Buildings Conference and Expo focused on plastics in construction. After the awe-inspiring and alarming presentations of the morning, described by Hattie Hartman above, in the afternoon the audience learned more about the way plastic and its breakdown products can enter, and potentially harm, our bodies – and about ways people in construction are working to reduce plastic’s impact.
Plastics in our bodies
Ben Humphries from Architype and ASBP Board member was particularly concerned about the impact of PVC, a product the firm endeavours not to specify: “PVC is made from toxic ingredients, it off-gasses toxins in use, and it is toxic to dispose of,” he said.
He quoted the Centre for Health Environment and Justice, which calls PVC “the most toxic plastic for children’s health and the environment”, and shared some recent research from the US on how compounds from PVC appear to get into children’s bodies. In homes with all-vinyl flooring, concentrations of the benzyl butyl phthalate metabolite in the children’s urine were 15 times higher than for children living in homes without any vinyl flooring. “Yet PVC is so often specified in nurseries!” Humphries added.
Plastics in fires
Professor Anna Stec from the Centre for Fire and Hazard Science at the University of Central Lancashire, who spoke at last year’s event, reminded the audience of just how toxic plastic is when it burns. Widely used synthetic polymers (derived from oil) burn more quickly when compared with natural materials (wood, wool, cotton, leather, etc.); they also generate more smoke and toxic effluents. Fire toxicity, from asphyxiants carbon monoxide (CO) and hydrogen cyanide (HCN), is known to cause the death of most fire victims in the short term. When a product contains halogens such as chlorine or bromine then fire irritants such as hydrochloric or hydrobromic acid will be also released.
Plastics are found in buildings in large quantities, in furnishing and contents, and in the structures themselves. And yet, as Professor Stec pointed out, while the products are tested and regulated for various fire characteristics (time to ignition, fire spread etc) the toxicity of smoke – which is actually the biggest killer in fires – is not regulated. Her department has studied the combustion behaviour of a range of different plastics commonly found in buildings, and she explained how the chemistry of different plastics altered the characteristics of the smoke.
Plastics containing nitrogen (such as polyurethane, or polyisocyanurate foams) give off hydrogen cyanide (HCN) when they burn. Asphyxia – or oxygen deprivation – is caused the inhalation of CO which binds to haemoglobin in place of oxygen, and by HCN which prevents oxygen uptake by cells. Oxygen deprivation results in confusion, loss of consciousness and eventually death. If CO is the only toxicant, death occurs between 50-80% COHb. Before that, exposure to 200 ppm HCN for just 2 minutes leads to incapacitation, said Professor Stec.
Polystyrene meanwhile contains little or nothing in the way of nitrogen or halogens – however, it burns very rapidly and when it does, releases huge quantities of dense black smoke, making it very hard for people to breathe or to see.
It is mandatory in the UK for plastic furniture and insulation to be treated with flame retardant. Although the intention behind treatment with flame retardant is to save lives, Professor Stec has also concerns about their use. Some of the halogenated and organophosphorus flame retardants do not stay in the products. They appear in household dust – which, as the audience in the morning heard from Dr Stephanie Wright, finds its way into our bodies.
Secondly, Professor Stec is concerned that while flame retardants do indeed inhibit the spread of flame, they do not necessarily inhibit the production of toxic smoke – in fact, her research has shown that some halogenated fire retardants dramatically increased the production of hydrogen cyanide from burning a sofa, meaning that occupants of a building may have less, rather than more, time to escape. As Professor Stec has warned, the long-term effects of the toxins generated in fires are particularly concerning for people who are exposed repeatedly through their work: firefighters, forensic investigators and clean-up teams.
Protecting others and ourselves – fire crews
The fires service in the UK is now waking up to this danger – thanks in no small part to the determination of concerned firefighters themselves. Scott Pearce of Kent Fire and Rescue described how, after reading that firefighters suffered increased rates of a number of cancers compared to the general population, he had been given the go-ahead to work within his own fire service and others up and down the country, to cut fire crews’ exposure to these toxins. “When I saw this data I realised we had to act; I approached my management and they put me in the lead of a project to tackle this in-house, even though I had never done anything like this before!” he said.
“Firefighters are a bit gung-ho, and the soot-covered face of the firefighter coming away from an incident used to be seen as a ‘badge of honour’. But actually, that fills me with dread. Soot is loaded with carcinogens and they can easily be absorbed through the skin.”
It was not only during fires that his colleagues were exposed to soot, Pearce found, it was also ubiquitous in their transport, and in fire stations. Following similar “clean side/dirty side” practices that are used to maintain hygiene in medical and food processing settings, Pearce had got his colleagues to rethink how they handled dirty equipment and protective clothing, so that the areas in the fire engines and fire stations where people spend time in everyday clothing, could be kept free of contamination.
The service has also tackled fire crews’ exposure to the same toxic gases that kill fire victims. While the fire is burning, fire-fighters wear full breathing apparatus, but after the flames are extinguished they may well re-enter the building without it. However, monitoring is showing that CO and HCN are still present in significant concentrations. While not enough to cause loss of consciousness, levels may be high enough to increase the risk of strokes and heart attacks – “and it is not unheard of for people to suffer heart attacks on duty.” Since the monitoring has been put in place, fire crews wear their breathing apparatus for longer, Scott Pearce told the conference.
Protecting the environment – the construction industry
Design & specification
Ben Humphries of Architype described how he and his colleagues take specifying decisions that enable them to greatly reduce the use of plastic in their buildings. The motivation grew originally from the desire to specify for health and good indoor air quality, but reducing life cycle carbon is equally important . Architype offers all its architects a bespoke database enabling them to consider both aspects of materials they are specifying – “though we are not a zero plastic practice”.
Because of its toxicity Architype do endeavour never to use PVC (discussed above) although it is so common in construction. “It is particularly popular in design and build because when costs are tight, it is so often the cheaper option.”
Referring to the ASBP’s own information resource on the lifecycle performance of uPVC windows, What’s in my UPVC frame, Humphries added “PVC windows don’t last very long, and they are impossible to repair,” meaning that even if they were cheap, they were not necessarily good value long term. This concern was backed by ASBP executive chair Gary Newman, who reported in his summing up that experience in Wales showed uPVC windows were replaced after an average of just 12 years – “is this really efficient?” he asked.
Other sources of information about low-toxin specification were in the Greenspec database, the Nature Plus certification scheme and, where they were available, environmental product declarations (EPDs). Gary Newman added in his summing up that the products accredited by ASBP patron member Nature Plus are plastic free – “and have been since 2002!” Considerations like these led to Architype’s distinctive specifications for the Enterprise Centre at the University of East Anglia: cladding not with plastic, or even timber (which usually has to be treated) – but straw and reed. Internally the building boasts clay plaster, hemp and even nettle furnishing fabrics, linoleum flooring, and a sprayed cellulose pulp in place of acoustic ceiling tiles
Ben Humphries said a 100-year carbon impact analysis had helped his team avoid the use of plastic floor coverings. “The analysis showed that the frequent replacement that is required for carpet actually outweighed the lifecycle impact of the floor structure!” The team decided to dispense with floor coverings altogether in many areas, instead opting for a finish of polished concrete – which won’t need replacing at all.
When construction products are being made from plastic, there are steps the supply chain can take to reduce some of the impacts. Jasper Hamlet of the environmental charity FIDRA addressed the issue of plastic contaminating the environment before it had even been turned into anything.
FIDRA focuses on the escape of nurdles. These are lentil-sized pellets of plastic that are manufactured from raw petrochemicals, and transported in bulk to be used to manufacture products. This manufacture and transport process is lamentably leaky: nurdles are spilled, wash into watercourses, and end up in the ocean. Nurdles have been found on 93% of the 1900 beaches searched by the charity and their volunteers – all over the world, and sometimes in their millions. Like microplastics, nurdles get mistaken for food wildlife, frequently found alongside broken plastic fragments in the bodies of dead sea birds, for example.
It is actually not hard to reduce this leakage to far lower levels, Hamlet said. At each of the roughly five steps between their creation and their conversion into the manufactured products where nurdles are handled and moved, leakage can be stopped, Hamlet said. Simple measures such as fine covers over drains, a discipline of sweeping and ‘hoovering’ spills immediately, and split-minimising packaging and handling techniques, are all set out in an agreement called ‘Operation Clean Sweep’. Checks by external auditors ensure that the nurdle ‘journey’ is loss free at each stage.
“Unfortunately of the 6000-odd companies in the UK that handle nurdles, only 150 are signed up to this agreement, Hamlet said. “Specifiers can definitely be putting pressure on their suppliers – and their suppliers’ suppliers – to sign up to this scheme and reduce the leakage.”
The role of clients was highlighted by Martin Gettings Head of Sustainability at Canary Wharf. They have encouraged suppliers to explore modular approaches to construction, which can greatly reduce waste on site. Their current focus is on consumer behaviour – tens of thousands of people work in Canary Wharf – so their energetic estate-wide programme has enabled them to divert a lot of coffee cups into the recycling stream – well over 3 million so far. They can also impose conditions on their tenants in the way they run their operations – such as requiring tenants to cut single-use plastics in their own operations.
Kris Karslake, Sustainability Manager at BAM Construct UK shared some of the practical issues BAM had come up against when trying to drive down plastic waste emerging from their operations.
The reality is that a lot of plastic is used of construction, and a lot is thrown away. So much comes from packaging: one of the biggest by bulk was the polystyrene protection from around white goods; but most materials and components arrive wrapped in plastic to keep them clean and dry.
The firm has undertaken audits and waste reduction initiatives. One surprise finding was following a temporary site accommodation refurbishment, a skip contained a significant amount of torn out plastic trunking, and discarded canteen plastic chairs. Was this a matter of poor design and procurement? Why couldn’t the wiring layouts be preserved (as they were in fact designed to be) – was this a failure of communication? And if the firm invested in smarter and more robust site furniture, perhaps it wouldn’t be skipped quite so readily? When materials do have to be discarded from construction sites, the majority can be recycled or recovered and even in some cases re-used. BAM has attempted to analyse its waste stream, and although by weight the plastic is not a major contributor – perhaps not surprisingly as plastic is light – “we know it has a very high impact on the environment so we have worked hard on the issue,” Karslake said.
While waste separation is usually seen as the best practice for recycling, to ensure the best quality ‘recyclate’ and therefore, the highest recycling rates, fitting in a range of skips for all the different wastes can be extremely difficult on a construction site. BAM’s waste contractor had assured the company they can separate the mixed recyclables they collect – “but from conversations I have had at this event, I am now not so sure”, Karslake disclosed.
When dealing with clean offcuts, rather than mixed construction waste, some manufacturers offered take-back schemes where material would be returned directly into the manufacturing cycle – flooring material for example, could often simply be melted and re-formed. Again, space (for storing offcuts for example) often presented an issue, but BAM nonetheless participates in a number of take-back schemes. Kris Karslake was also faced with weighing up the pros and cons of specifying plastic. Standard timber pallets might seem preferable to plastic – but, he explained, they don’t get re-used, while plastic pallets do, and they are also lighter, reducing the fuel consumption of transport. “We really need to do full life cycle studies for questions like this’” he explained.
All the speakers made it clear that good science, and responsive and supportive management, were crucial to reducing the impact of plastic in construction – without simply adding to another burden of damage elsewhere. The piece of the jigsaw clearly lagging, however, was regulation and legislation. Hopefully these successful, innovative exemplars can give the lie to the tired old excuse that regulation is a ‘brake on enterprise’. There is, as they say, no profit to be made on a dead planet.
Gary Newman, ASBP Chair, thanked all the speakers and reminded everyone that the ASBP Plastics working group meets on 3rd April, 11.00-15.00.