Sustainability is the well considered use of materials and resources today for the benefit of the generations of tomorrow. No thinking about future issues can be complete without fully considering the implications of sustainable options. In particular, whole life assessment is crucial to the foundations of sustainability. At this stage of the early part of the twenty-first century, sustainability is one of the top-line subjects: not only does it involve the essential issues of carbon and climate change, it also focuses our attention on the use of raw materials, water and land. It is absolutely vital that when we expend resources, they must be employed well and to the maximum overall benefit. The role of whole life assessment value and cost is central to this task and must taken seriously. It is essential that sustainable issues are part of the core agenda within any whole life

value or costing appraisal. Sustainable thinking and practical application are the most challenging issues in today’s construction industry. It is vital that methods and principles are adopted that embody a sustainable approach. Assessment of whole life value is an important aspect of this significant area. Understanding how a building will perform, or at least obtaining a reasonable assessment, is invaluable in this area. From every perspective, to maintain the status quo or ignore the issues that we are creating for future generations is plainly absurd. Sustainability and whole life value are obviously interconnected, the latter being a

fundamental affirmation of the former. Ensuring that the life of a building is appropriate is at the heart of sustainable thinking. There is little point in devoting resources to the construction of any project unless they are of benefit. As resources become limited, there is an increasing need to understand that they can be put to good use over a relatively long timeframe. Justification of the application of resources must be in proportion to the prescribed life. However, we often see constructions that use the lowest performance values and expect to achieve long life values when they plainly will not do so. Growing political pressure to ensure sustainable options are adopted makes the need

to regulate increasingly certain. There is every reason to believe that shortly this will become part of legal requirements under the development of the Secure and Sustainable Buildings Act 2004 – this Act has achieved Royal assent but no provisions have yet been put in place. Until and unless this takes place, it is uncertain whether there is enough momentum to drive involvement in the subject to the level needed. Many buildings have a notional life that will be established by a project specification

reflecting the client’s requirements. Particularly in the case of commercial buildings, the need to be accurate and accountable is essential to the viability of a project. The client and funders need to have confidence that the design life has been established

realistically. However, little or no account is currently taken of the real cost of this period – which includes accurate demonstration of the potential issues and the various outcomes that will have a life-modification effect and cost. Logically, there is never going to be one answer to this question, and single answers should be regarded with suspicion. A range of answers is, however, both realistic and potentially very useful. In attempting to establish an answer to the fundamental question of what period of

life is required, the common answer is ‘as long as possible in proportion to the financial cost’. That is to say we should specify and build to the best level of quality and robustness that the project can stand. This is because to do otherwise is wasteful in the extreme and highly unsustainable. Often not enough time is spent on this issue. Despite this inescapable logic, this is the situation for the majority of buildings cur-

rently. Any sustainable threads are a consequence of other drivers or are purely fortuitous. Only in very recent times have there been any real attempts to ensure a building’s life is as long as possible, therefore maximising the resources and materials used in its creation. Life costing and the establishment of future performance is of considerable importance

to sustainability – it is potentially the key driver. It is not unreasonable to assume that in the near future there will be a requirement to demonstrate as small a carbon footprint as possible, that will include a clear understanding of every component’s life. The importance of ensuring efficiency with regard to every element of a project is clear – but how is it to be achieved, in the face of existing pressures and inaccuracies? As the pressure for greater efficiency increases, considering every construction as a

resource for the future is becoming the norm. Analysis of the resource’s potential is likely to become established as a key driver, in the same way that carbon footprints have currently taken over from simple energy-use calculations. The need to be more sophisticated is pressing and essential. We cannot afford to

squander resources, effort or time in the pursuit of values that do not really deliver results. Many current approaches to this problem are very crude, either taking too simplistic an approach, or using a model that is far too specialised and complex for everyday application. One related area that can be seen as analogous to this conundrum is the analysis of

energy in buildings. The majority of energy considerations, until relatively recently, concern simple heat-loss and heat-gain, largely through the mechanism of U values (the U value measures the heat flow through a building element under steady-state conditions that limit its accuracy in comparison with real-world energy flow, which is always changing). Ensuring that energy and waste are considered and managed intelligently is essential. Energy use in production, embedded energy, and the energy in use as the building is

occupied are obviously of importance. The longer lived the building and the poorer its performance, the greater the cost to the environment. A building should therefore be as efficient as it can be. The life of a building’s components is exactly the same, but less quantifiable.