CO2 pricing provides incentives for investments in climate-friendly heating technologies and energy-efficient renovation. But a tax on greenhouse gases or an emission trading system alone will hardly be enough to make them economically attractive. Additional policy instruments are needed to do justice to the special features of the building sector. These are the key findings of a study conducted jointly by the Institute of Energy Economics at the University of Cologne (EWI) and the Institute for Public Economics at the University of Cologne (FiFo) on behalf of the Zentraler Immobilien Ausschuss e.V. (German Property Federation) (ZIA).