The current worldwide climate change situation motivates researchers to look for solutions to reduce its impacts on the environment. One of the solutions is the increase of energy performance and efficiency especially in buildings in respect to environmental norms. In this aspect, the Wal-e-cities projects funded by ERDF (European Regional Development Fund) aim to create smart tools in terms of connectivity, governance, living environment, mobility, energy and environmental impacts, for the Walloon Region in Belgium (Europe). The smart energy management in Wallonia will contribute to reducing problems related to the increase of pollutions due to buildings energy consumption. This paper is a part of the Wal-e-cities_energy project and focuses on the heat consumption and demand assessment of residential and tertiary buildings in Wallonia. The heat consumption data coming from the regional energy reports were used to estimate the heat consumption and heat demand of each residential and tertiary building type. Thereafter, these estimates combined with cadastral data and territorial data were spatialized on the urban region of Liège. The heat demand and consumption assessment is modelled at the building scale for the urban region of Liège, but it is represented on geographical maps on a statistical sector scale. For residential buildings, the heat consumption and demand are mainly related to the number of buildings in the statistical sectors, whereas for tertiary buildings the type of building also has a paramount influence. In addition, the difference between the heat demand and the heat consumption of the different types of buildings varies in a narrow range, between 15 and 18% for residential buildings and 16 to 18% for tertiary buildings.