Previous life-cycle studies of buildings tended to omit the phases after demolition. If recycling is not included, the potential benefits of recycling are not possible to assess. A parametric study of a one family house is presented which focuses on the potential energy savings by recycling the various building materials after demolition. The results indicate that it can be more important to design a building for recycling than to use materials which require little energy for production, that the creation of effective recycling depends upon its consideration and inclusion at the design stage, that the re-use and adaptation of existing foundations is an important component of recycling.