The trade body representing manufacturers of aggregate concrete building block in Great Britain. The Concrete Block Association (CBA) is the trade body representing an industry producing around 60 million m2 of dense and lightweight aggregate concrete building blocks per year. Concrete blocks continue to adhere to all relevant building regulations and are available in various strengths, weights, and surface textures. It’s not surprising that they continue to be the best selling house building block in the UK, recommended by architects and specifiers as the block to use for a successful build.