The present disclosure provides building structures. A building structure can comprise a plurality of modules. An individual module among the plurality can comprises a plurality of wall panels. One or more wall panels of the plurality of wall panels can comprise undulating outer surfaces that each conform to an undulating outer surface of an adjacent module. The building structure can further comprise a binding agent in one or more void spaces between the plurality of modules. The binding agent is configured to maintain the plurality of modules in proximity to one another. The building structure may contain components to increase the energy efficiency of the structure.