The energy flows associated with the materials comprising a building can be a significant part of the total energy used in a building's life cycle. Buildings have finite life spans, and the materials from demolished buildings can be either a burden that must be disposed, or a resource that can be used. In this paper we analyse the end-of-life energy impacts of concrete, steel and wood. End-of-life options considered include reuse; recycling; downcycling; energy recovery; and disposal in landfill. We follow the life cycles of the building materials from the acquisition of natural resources through to the end of the product's life cycle. We identify possibilities and constraints for integrating more effective end-of-life material processing options into existing industrial systems.