Contempra (Portland-Limestone Cement): A New Lower Carbon Cement
Reflecting the cement industry’s commitment to being a proactive partner in finding solutions for a low carbon future, Contempra is a new cement that reduces CO2 emissions by 10% while still producing concrete of comparable strength and durability to concrete produced with regular Portland cement. Contempra is recognized under the name Portland-limestone cement in CSA cement and concrete standards. Introduced in the Canadian market in 2011, Contempra is today rapidly becoming the preferred standard for the majority of new construction projects in Canada. Once it is used for all suitable applications, Contempra will reduce CO2 emissions by up to 900,000 tonnes annually. This is equal to saving over 347 million liters of gas. Or planting 23 million trees.
While still relatively new to the Canadian market, Contempra has an extensive proven track record in Europe — where it is known as Portland-limestone cement — in a variety of commercial and residential applications for over 35 years.
Contempra is referenced in the National Building Code through the CSA A.23.1 standard under the name Portland-limestone cement. With recent changes in the CSA A23.1-14 Standard, concrete containing Portland-limestone cement is now permitted for used in sulphate exposure environments. PLC-based concrete used in such exposure environments must first meet the mix designs requirements of the CSA A23.1-14 Standard and pass sulphate quality assurance tests as well.
Environmental Product Declaration
Environmental Product Declarations measure a wide range of environmental impacts (for example, greenhouse gas emissions, toxic substances, habitat destruction, water impacts, ozone depletion, etc.) at every step of a product’s life cycle ? from raw material extraction and processing, to manufacturing, distribution and disposal or recycling at end of life.
The Cement Association of Canada has registered an EPD for Portland-limestone cement (branded as Contempra in Canada) with the CSA Group. The cement EPD, which was prepared by the Athena Sustainable Materials Institute, can be viewed on CSA Group’s EPD registry listings.
Environmental Life Cycle Assessment of Portland-Limestone and Ordinary Portland Cements in Concrete