Cement-free concrete block promises 73% carbon saving

Greenbloc (Image courtesy of CCP)

A new cement-free carbon block offers a 73% CO2 emissions saving compared to traditional concrete blocks, its manufacturer has claimed.

The new sustainable concrete block, Greenbloc, is being launched by CCP, part of SigmaRoc.

Greenbloc is a high-density load-bearing concrete block made from class 1 aggregates and Cemfree, a cement-free alternative to conventional concrete.

CCP said the block is manufactured to BS EN 771 – 3: (2011) and complies with Part E of the Building Regulations for walls and floors. It is manufactured, stored and placed in the same way as conventional concrete blocks and there is no compromise on strength compared to ordinary Portland cement (OPC) blocks, CCP said.

CCP’s figures suggest that, for an average three-bedroom house, OPC accounts for almost 3.7 tonnes of CO2. In comparison, Greenbloc accounts for 981kg of CO2 for the same house, achieved through a saving of 1kg of CO2 per block and adding up to a total saving of 2.7 tonnes of CO2 per house.

Michael Roddy, managing director at CCP, said: “Greenbloc is a game-changer for the construction industry. Up until now, sustainability has all-too-often been focused on operating carbon emissions post-build, rather than the carbon generated during the build schedule and in the manufacture of building materials. Greenbloc is an important step in the greening of both construction projects and the wider supply chain, as it has the capability to reduce CO2 by up to 73% on a project compared to OPC. In short, the only difference to OPC is that Greenbloc has the ability to dramatically reduce CO2.”

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  1. How will the cost compare with – say – typical 7N concrete blocks?

  2. This is a near-worthless, puffed PR piece. So, what is this secret ingredient (aka “Chemfree”? More specifically, what its monetary cost????????????????????????

  3. Good news for sustainability
    I will promoted to my work team

  4. Tony, thank you for your comment. I have been awaiting details about cost from SigmaRoc. The only detail we have is that there will be a “slight premium” for the cement-free alternative. Full pricing will be available from the local merchant suppliers.

    Greenbloc is the same dimensions as an N7 block (100mmx440mmx215mm), and SigmaRoc claims it has the same characteristics, including weight. It has the same thermal and strength characteristics of a conventional load bearing concrete block.

    Richard, the “secret ingredient” is the cement-free binder Cemfree. More details can be found here:

  5. What are the insurance implications for using this material?

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