The energy requirement of an existing small scale district heating (DH) network, connected to seven properties of mixed use (office and living spaces), located in Nottinghamshire and fuelled by a 300 kW biomass boiler, was studied in view of upgrading it. This paper presents results of heat energy simulation, monitoring and an energy audit of the existing heat network. The individual properties’ heat load profiles were modelled in order to get an aggregated site profile network. In addition, on selected points of the network, the operating conditions of the network were monitored and collected: supply/return temperatures and mass flow rate are presented. The paper also summarises a recommendation for an upgraded heat network, focusing on improving the DH and to propose this as a solid technology for the future challenges of the heat energy market.