Whole-life thinking is an essential component of sustainable design. The idea is very simple: when comparing alternative designs for a construction project, don't just focus on minimising the initial investment, but select the alternative that performs best over the building's life cycle.

To assess whole-life value you have to balance capital costs against future benefits. This is a problem because the future cannot be predicted with certainty. The standard method of whole-life costing assumes that data about the future is available, so the method is of limited value. Cambridge Architectural Research has developed a new approach to whole-life costing which takes account of future uncertainty.

The amount of uncertainty is crucial. When there is high uncertainty there are two consequences:

• future benefits are devalued, reducing the level of capital investment that can be justified
• lifecycle options become increasingly attractive

A durable and efficient design often gives better whole-life value than lower specification alternatives, but not always. Investing more doesn't necessarily give good value: hence the need for a systematic approach to whole-life assessment. The basics of whole-life assessment apply equally from a cost-effectiveness or a CO 2 -savings perspective.

To use whole-life assessment in practice, architects should understand the method's fundamental principles and techniques, and also its limitations. This will be explained at the seminar, together with worked examples and exercises.

Speaker
Dr William Fawcett, Cambridge Architectural Research Ltd