Already acknowledged as a highly sustainable substance, the Gypsum Industry is working hard to improve further its sustainability credentials and aims to rationalise its efforts in conjunction with the relevant operators in the construction chain.
Extracting and Processing Natural Gypsum
Gypsum/anhydrite are produced from open-cast mines or underground mines using pillar and stall mining methods that give extraction rates of up to 75%. In the UK and Ireland all extraction is from underground mines.
Sourcing and Processing FGD Gypsum
FGD gypsum is an alternative to natural gypsum that comes from the flue gas desulphurisation plant (FGD) of the power station industry. FGD gypsum is the end product of a wet purification procedure with natural lime, that essentially forms according to the same laws as natural gypsum – but in a speeded-up process taking only a few hours.
FGD gypsum has a higher purity (gypsum content of 96%) than most natural gypsum (80%). This means that lower quality gypsum can be blended with high purity desulphogypsum, allowing material that would not have been mined in the past to be classified as exploitable reserves.
Gypsum products and solutions used every day are designed to:
- Be manufactured using by-products and recycled materials;
- Be manufactured with low energy intensity;
- Be manufactured with low emissions. The main emission of the production process is steam;
- Use little packaging;
- Be recycled at the end of their life cycle;
- Promote indoor air quality;
- Be sound insulation efficient;
- Be impact and fire resistant;
- Be energy-efficient in its use – thereby playing an important role in the reduction of carbon emissions in the built environment;
- Extend the lifetime of a building thus enhancing overall sustainability.
The gypsum Industry takes advantage of the eternal recyclability of gypsum to move the construction chain towards a positive environmental footprint.
GPDA members have invested both directly and through third parties to provide routes for segregated, clean plasterboard waste to be delivered to reprocessing stations. Access to natural resources is enhanced by developing outstanding construction and demolition waste management to divert construction and demolition waste from landfill, applying the waste hierarchy (prevent-reuse-recycle-recover-dispose) in accordance with the life-cycle impact of gypsum products and systems (from cradle to cradle).
Waste Prevention: Design for Construction
- Promotion of an efficient and interactive dialogue with Construction Site Managers for proper storage, handling, sequencing, fixing and finishing of gypsum products and systems;
- Promotion of demountable and reusable partitions for commercial buildings;
- Promotion of, whenever feasible, bespoke size boards (plasterboards, fibreboards and blocks).
Waste Disposal Reduction Measures: Design for Deconstruction
- Promotion of research and development for the design of gypsum products and systems which ensure that recycling is maximised, ie that diversion from landfill is taking place effectively;
- Promotion of selective deconstruction and sorting amongst the relevant stakeholders and more particularly the demolition industry;
- Promotion of research and development for ensuring the proper recycling of gypsum demolition waste;
- Optimisation of the internal recycled material input capacity of gypsum manufacturing plants.
GPDA Statement on Plasterboard Recycled Content
Plasterboard is a highly sustainable product: new plasterboard may have a recycled content of almost 100% and nearly all plasterboard is 100% recyclable after use. As a result, plasterboard often has the highest recycled content of any of the construction products in a new building.
Origins of Recycled Content
According to the internationally accepted definition in ISO14021, recycled content in plasterboard can derive from 3 sources:
- Secondary fibre in the plasterboard liner, accounting for up to 5% by weight
- Post consumer gypsum recovered from construction or demolition site waste, typically accounting for 5 – 15% (and subject to a technical limit of around 25%),
- By-product gypsum from Flue Gas Desulphurisation (FGD) or other industrial processes.
The GPDA makes no distinction between products containing gypsum from different sources as the performance of the plasterboard products and drywall systems are unaffected.
Average recycled content of gypsum products manufactured in the UK rose to over 80% at its peak in 2014, making plasterboard systems a major contributor to sustainable building in GB. With the reduction in FGD gypsum since then, the figure is now just below 50% and expected to reduce further as coal fired power stations close.
All 3 UK gypsum manufacturing companies now have BES6001 certification, contributing towards responsible sourcing (Responsible Sourcing of Materials section in BREEAM 2011, Section 9 : Mat 3).
In order to protect the environment, preserve resources and promote the long term interests of stakeholders, the GB plasterboard industry is highly motivated to build upon its leading position in resource efficiency with further improvements:
The ground-breaking Ashdown Agreement on Plasterboard Recycling, signed with WRAP in 2007, has resulted in an ongoing increase in the average recycled content.
The change in the landfill guidance from 1 April 2009 required that visible plasterboard waste cannot be disposed of in general landfill but must go to a non-hazardous mono cell. The greater cost of such disposal has increased the demand for cost effective closed-loop recycling.
The plasterboard industry also promotes greater recycling through its support of the Environment Agency & WRAP Quality Protocol programme, and the successful development of BSI PAS109: 2008 “Specification for the Production of Recycled Gypsum from Waste Plasterboard”.
The Plasterboard Sustainability Partnership (of which the GPDA is a founding member) is working with the Defra Sustainable Products & Materials (SPM) team to improve further the sustainability of plasterboard products across all life cycle stages. The industry product stewardship approach will be kept under review as cradle to grave life cycle models are further refined.
Conclusion and Outlook
The GB plasterboard industry is building upon its lead in Europe and thereby improving the sustainability of all buildings in which plasterboard is used.