The Concrete Block Association (CBA) is signed up to the British Precast Sustainability Charter which drives manufacturers to go beyond legislation and take voluntary actions to make their products and operations more sustainable. Responsible designers or contractors can specify and procure concrete blocks produced by members of the CBA with confidence.
Due to their inherent sustainable properties and the efforts made by members, the use of concrete blocks will result in buildings that are resilient, safe, strong, adaptable and have a long lifespan compared to other forms of construction.
The materials used to make concrete block products come from natural and recycled sources. In 2015, almost 20% of the materials used in block production came from recycled secondary sources. Most of our materials, virgin or recycled, require only minimal processing to render them suitable for use, thus concrete blocks have a relatively low embodied energy value, unlike highly processed materials such as polymer-based products.
Responsible local sourcing
The responsible sourcing of materials is a key concern across the construction sector. Currently over 70% of CBA members’ production is certified responsibly sourced to BES 6001 level (all having at least a Very Good rating). This ensures that the sustainability and product stewardship is addressed throughout the supply chain.
Local sourcing is the cornerstone of concrete block sustainability. Most of the UK demand for concrete blocks can be met locally, so there is no need to import materials from thousands of miles away – avoiding the potential environmental impact from logistics. The local availability of aggregates makes for low carbon footprint deliveries to the factory. In fact, the concrete sector does its best to utilise rail and rivers to transport millions of tonnes of aggregate every year in the UK. Member’s commitment to sustainability is not only environmental. Local sourcing also supports regional economies and local employment providing a social benefit.
Sustainability in the block factory is about improving resource efficiency, reducing waste and ensuring that environmental management systems, those compliant to ISO 14001 for example, are maintained. Over 85% of the CBA members’ production is covered by the Environmental Management standard ISO 14001. Environmental management not only helps with environmental permits and law compliance but also drives continual improvement and enhancement of performance. Closed loop manufacturing systems minimise any outgoing waste resulting in 98% of waste at block factories being recycled and diverted from landfill, whilst preventing any waste effluent streams.
Members of the CBA are committed to fully understanding the embodied carbon impact of their products. As product sustainability moves more towards a whole life approach and beyond in the form of life cycle analysis and the circular economy, it is important that we collect accurate carbon data. Evidence of this commitment can be found in member’s involvement in the British Precast Environmental Product Declaration project. Preliminary results of this project show that many of the current sources of carbon inventory data are over-estimating the impact of concrete products. During their service life, concrete blocks will effectively re-absorb much of the carbon dioxide that was released to create them through a process called carbonation.
During use, the higher thermal mass of masonry constructed buildings results in less severe seasonal temperature fluctuations within the building. This means reduced reliance on additional heating or cooling systems to maintain comfortable temperatures and the associated energy consumption when compared to lighter weight framed or panel-built alternatives.
Environmental Product Declaration
The CBA generic cradle to grave Environmental Product Declaration (EPD) covering the full range of aggregate concrete blocks (Ultra lightweight, lightweight and dense) can be found here.
The whole life cycle should be taken into account when considering the sustainability aspects and impacts of construction products and assessments should not be undertaken based on single indicators.
The choice of block in a building or structure means that resilience and adaptability are built in. The inherent properties of the material help it to withstand all weather conditions, infestations, flooding & fire.
As part of British Precast, the producer members of the Concrete Block Association are signed up to the British Precast Sustainability Charter and are subject to annual verification audits of manufacturing and data. This data is compiled into Key Performance Indicators (KPI’s) to enable performance benchmarks to be set and annual reports published. Member companies are required to set objectives and targets to continually improve their sustainability performance. This data collection and review will help block producers meet future sustainability challenges and increased digitalisation.