CEM I Portland Cement: Pure Clinker Grade EN 197-1

CEM I — Portland Cement

Pure Portland cement according to EN 197-1 with at least 95% clinker content. Highest early strength but also the highest CO₂ footprint of all cement types.

CEM I is classical Portland cement according to EN 197-1 with a clinker factor of 95–100%. No blast furnace slag, no fly ash content — only cement clinker produced by high-temperature firing plus up to 5% minor constituents.

Advantages: highest early strength, rapid setting process, universally applicable. Disadvantages: high CO₂ emissions per ton, entirely from the clinker. For modern, climate-optimized projects, CEM II- and CEM III-cements are gaining prominence — see also our topic portal CO₂-neutral concrete.

Typical applications: precast elements, fast-setting screeds, winter construction with frost risk.