There is a large consensus concerning the expected trend, if not the magnitude of change, of the UK climate in the coming decades [Climate Change 2007: Impacts, Adaptation and Vulnerability, Intergovernmental Panel on Climate Change, April 2007]. This study aims to quantify how such changes will have a direct effect on heating and cooling energy use in future office environments (i.e. by the year 2030). When considering future offices, it is also necessary to account for a change in the small power and lighting equipment being used, in this case by assuming an improved efficiency in both categories. This will also have a significant effect on the balance of heating and cooling an office. Furthermore, the subtle effect of a change in location within the UK can affect results further, with northern cities having substantially higher heating loads (and lower cooling loads) than southern locations. Such factors can influence approaches towards reducing future office energy demands and, in some cases, be the difference between a heating-dominated or cooling-dominated building. This study should also inform future choices for supplying energy to office buildings, in particular microgeneration options. It confirms the importance of dealing with demand-side changes before assessing the supply-side opportunities, with buildings having very different heating and cooling needs post-refurbishment. The study also highlights the importance, and possibilities, of adapting to future climates, and the benefits of promoting heating-dominated buildings instead of cooling-dominated. (C) 2007 Elsevier B.V. All rights reserved.