Get Sust! Issue 27

Greener cement

Civil and Marine took a stand at this year’s EcoBuild event in order to remind designers and specifiers that there are more environmentally friendly cement options available right now.

The company has been manufacturing ground granulated blastfurnace slag (GGBS) since 1982. Blastfurnace slag is a by-product of the iron industry. The company’s manufacturing process takes this waste and turns it into a cementitious materials that can be used to displace Portland cement in concretes, mortars and grouts. Indeed, it has been use in a ‘within-mixer blend’ with Portland cement since the 1960s, and its physical properties are particularly beneficial in projects where sulphate and acid attack are likely. Civil and Marine also says that the off-white colour of the GGBS helps to soften the visual impact of large structures such as retaining walls.

But the real advantage for designers is that all they need to do is ask for the product. It’s already used in around a third of all UK deliveries of ready-mix! From the construction point of view, it’s no different to conventional cement, but environmentally it’s quite different - with an EcoPoint score of 0.47 compared to Portland cement (EcoPoint 4.6).

Learn more:

	•	Details are at www.civilandmarine.co.uk.
	•	Find out about BRE’s EcoPoints life-cycle environmental profiling from www.bre.co.uk/envprofiles.