Disposing of polystyrene
A heated debate on old insulation
An agitated mood reigns amongst building firms nationwide. The reason: On 1st October, the German Bundesrat (Federal Council) opted to tighten an existing EU regulation by reclassifying flame retardant HBCD as “hazardous waste”. Insulation panels containing this substance – which had been used for decades to insulate the facades of domestic properties – were suddenly to be treated as special waste. As a result, the disposal of expanded polystyrene (EPS) containing HBCD was set to become significantly more complicated – not least because building materials containing more than 1,000 mg / kg of the flame retardant would have required their own container on the construction site. What’s more, they would only have been permitted to be thermally processed at incineration plants with the corresponding approvals.
According to the Federal Association of the German Waste Management Industry (BDE), this would have affected up to 60,000 tonnes of insulation waste annually. After loud protests from all sides, the responsible persons have now backtracked. Polystyrene insulation can continue to be disposed of alongside normal building waste – for the time being, at least, since this may well not be the last word on the issue.
HBCD – the undesirable flame retardant
The substance that triggered the discussion was hexabromocyclododecane: a brominated chemical that is mixed predominantly with polystyrene insulation to render it inflammable. During this process, HBCD is bound to the chemical structure of the material and cannot leach out during normal use of EPS products and under normal temperature conditions. In insulating materials, therefore, it poses no risk.
However, hexabromocyclododecane is inherently poisonous and is not easily bio-degradable. If HBCD-treated insulation materials are disposed of in landfill sites, this substance can enter the groundwater and accumulate in organisms.
For this reason, since 2008, the compound has been listed as a PBT substance of particular concern. “PBT” stands for “persistent”, “bioaccumulative” and “toxic”. In 2013, HBCD was globally classified as a “POP” or “persistent organic pollutant”. For this reason, the production and sale of HBCD has been prohibited since 2014 under POP regulations, with one exception: the flame retardant may continue to be used in EPS thermal insulation until 2018, which is why HBCD disposal looks set to remain an issue for the foreseeable future.
HBCD disposal can be costly
The recent classification of HBCD as “hazardous waste” would have rendered the treatment of building waste significantly more complicated. The reason: that Germany’s Closed Substance Cycle Waste Management Act requires the strict separation and separate disposal of hazardous substances. Most incineration plants would not have been able to accept polystyrene waste, since they do not have the necessary technology and approvals to carry out regulation-compliant HBCD processing. This, in turn, would have affected the costs: due to the increased incineration price, which was set to rise as high as 4,000 euros per tonne, the BDE estimated the additional burden on building firms at up to 240 million euros per year. This is twenty times as high as the current disposal costs for mixed building waste, which lie at around 200 euros per tonne.
In the interests of avoiding this impending crisis, the Federal Ministry of the Environment has now softened its position: Until further notice, insulation containing HBCD must not be separated from other building waste. Construction waste with up to 0.5 cubic meters of HBCD insulation panels per tonne is not classified as “hazardous waste” and may continue to be processed thermally in waste incineration plants. Other countries have been requested to issue corresponding decrees.
Even if the disposal problem has been averted for the moment: Those wishing to ensure that polystyrene panels are free of HBCD should check the product labelling, since the flame retardant’s status as a PBT substance is required to be listed here. As an alternative, building firms can use an online form from the Federal Environmental Agency to ask manufacturers and traders whether their EPS insulation contains HBCD. If documents are no longer to hand, a definitive answer can only be obtained through chemical analysis. Quick tests have now been developed for this purpose and can be carried out directly on site.
Alternative fire protection
The rigid foam EPS is unquestionably the number one choice for facade insulation. Since the prohibition of HBCD, therefore, the industry has worked on developing alternatives. For many years now, the alternative flame retardant PolyFR – a non-toxic, non-bioaccumulative plastic with bromine additive – has been used to achieve the requisite classification of “flame retardant” without the addition of HBCD. Thus, builders can continue to insulate their facades with polystyrene without having to worry about the potentially costly future disposal of HBCD.
Those who want to be on the safe side and renounce synthetic materials completely can opt for ecological alternatives. As well as being excellent insulators, cellulose, hemp and wood fibres are safe to use, easy to recycle and permeable, regulating humidity and helping to create a healthy indoor climate. Of course, an “eco” building need not go without fire protection. Special product solutions tackle the problem holistically: Fire-resistant coatings made of cement-like, intumescent systems preserve the stability of the building structure and protect the home and its occupants.
The outlook is good
The happy news: For now, it looks like house builders – who are responsible for disposing of old polystyrene – will avoid taking the hit. Living in a polystyrene-insulated home is safe, even when the polystyrene contains HBCD. Those who want to be sure of avoiding additional costs in the future should use EPS insulation panels with PolyFR, which appears to be unproblematic as a flame retardant and is equally as effective. An appealing alternative in many respects is the use of environmentally-friendly building materials combined with holistic fire protection concepts. Healthy living environments are currently in the spotlight – which is why it’s worth taking a closer look at the various options for “healthy living” construction.