While many countries have set ambitious targets for reducing energy use and GHG (greenhouse gas) emissions, it remains highly uncertain whether the policies introduced will be suitable to reach these targets at the specified times. Models used to inform building policies often do not account for the different boundary conditions related to socio-economic development, climate, composition and age structure of the existing building stock, and lifetime expectancy, which hinders effective strategy development and realistic target setting. This study presents a dynamic Type-Cohort-Time (TCT) stock-driven modelling approach that considers demographic aspects, lifestyle-related issues, and building-specific characteristics. Case studies were conducted for the dwelling stocks in Germany and the Czech Republic, two countries with different boundary conditions, but that are sheltered under the same European energy-reduction policies and goals. The effects of the policies on nearly zero energy buildings and increased renovation rates were tested. The results showed that current regulations are sufficient to achieve the 20% energy efficiency goal by 2020, but not to reach the 2050 energy and GHG-emission goals. The scenarios further demonstrate that the same policies on renovation and construction in different countries lead to different energy reduction levels. Accordingly, country-specific policies and measures are suggested.