Valuing embodied energy in the conservation of historic residential buildings
Authors: Pullen, Stephen; Bennetts, Helen
ABSTRACT: Conserving buildings rather than demolishing and rebuilding them avoids energy consumption and greenhouse gas emissions which would result from the embodied energy expended in providing new construction materials and components. This paper explores the potential environmental advantages of conserving buildings particularly in the area of historic dwellings. To retain the distinct character of older suburbs, some local councils are seeking to persuade residents to renovate older houses rather than demolish and re-build. The paper describes research which uses a late 19th century stone villa as a case study for a desk-top analysis of life cycle energy consumption, greenhouse gas emissions and costs. Two scenarios are considered which are (a) renovate and extend and (b) demolish and re-build to a similar design. The results show that the life cycle emissions of the renovated/extended villa are 26% less than the demolish/re-build scenario. In addition, the renovated/extended villa scenario is moderately less expensive. The combination of lower cost and emissions may be sufficient to influence residents to retain historic dwellings although there are definite advantages of a completely new building and the paper comments on further inducements to discourage the demolish/re-build choice.