Sector coupling is seen as one of the keys to improve energy efficiency within urban centers. In this perspective, residential energy system coupled with industrial waste heat recovery via district heating network is a promising solution. However, it also implies the coordination between systems design since a decision taken in one subsystem directly affects the decision-making of other subsystems. The aim of this paper is to demonstrate the sector coupling within an energy community containing an industrial site. The problem is formulated as a renewable energy hub with investment and operation decisions. Each building is modeled individually and the Dantzig-Wolfe decomposition is applied to optimize the district-scale problem. The industrial site is modeled as a heat source with fixed capacity and temperature. The marginal cost analysis demonstrates the spillover effect of waste heat availability on the profitability of PV panels, therefore engendering a self-consumption competition.