Every building and every district is different. The primary school around the corner can loose half of its heat just because of a poorly insulated floor, while the terraced houses next door burn large amounts of natural gas due to leakages in their roofs. At the same time, it may turn out that a heating network is financially interesting for the older part of the district, while the rest of the houses are better off with a heat pump. Every building and every district require a suitable strategy. Using our earlybirds’ NEST model (building model) and COLONY model (district model), we look for the right measures at the right time while putting the interests of residents and building owners first.