Yes sorry I didn't cite my source - it is per weight: https://www.sciencedirect.com/science/article/abs/pii/S1350630714000387?via%3Dihub https://www.sciencedire

Yes sorry I didn't cite my source - it is per weight: https://www.sciencedirect.com/science/article/abs/pii/S1350630714000387?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S13506... Per tonne, twice as much concrete is used per year than all other building materials (including wood, plastic, metal) combined.