The RentalCal project focuses on the current level of energy efficiency investments in the rented housing sector, which is in danger of missing EU policy targets. RentalCal will show a clear road map towards a sustainable housing stock and is developing models and tools for assessing the commercial viability of energy efficiency retrofitting in rental properties. This will reduce split incentive barriers - translating the positive effects of energy efficient and sustainable construction into real value and financially feasible investments for the real estate industry.