British engineers have developed a new environmentally friendly cement that is carbon-negative | Environment | guardian.co.uk

Now this looks really potenially a kind of win-win thing: read about it here British engineers have developed a new environmentally friendly cement that is carbon-negative . And the reason for optimism is, in a nutshell: "Novacem's cement, based on magnesium silicates, not only requires much less heating, it also absorbs large amounts of CO2 as it hardens, making it carbon negative."
Now this is worth putting in a broader perspective: "Making the 2bn tonnes of cement used globally every year pumps out 5% of the world's CO2 emissions - more than the entire aviation industry. And the long-term trends are upwards: a recent report by the French bank Credit Agricole estimated that, by 2020, demand for cement will increase by 50% compared to today."
It'll all come down to cost and availability, I guess. And it may also be worth keeping an eye open for the particular material qualities of the 'crete compared with other materials. One commenter on the article mentions the conservatism of the building industry as a likely retrogressive force...