1.1 What this Book is About
Cost Studies of Buildings is about the understanding and application of costs to buildings and other structures. One of its aims is to ensure that scarce and limited resources are used to best advantage. It is about ensuring that clients receive the best value for money for the projects they construct. As buildings have become more complex and clients have become sophisticated and better informed, the techniques and tools available have become more extensive. The use of information communication technologies (ICT) have also provided a new array of possibilities, particularly in the ease of modelling different design and construct solutions.
The book has been divided into three sections for clear understanding of theoretical underpinnings and practice.
1.1.1 Section 1: cost control
The first of these provides a context for the material that follows later. It includes a simplified analysis of the construction industry since building costs cannot be studied in a vacuum but need to be considered within the industry to which they are applied. A more detailed historical study of the industry can be found in The Construction Industry of Great Britain by Roger Harvey and Allan Ashworth (Butterworth-Heinemann 1997). It has also been thought appropriate to include a brief history so far of the subject of building economics. The subject material in general is provided under a number of different titles and descriptors. It has variously been described as building economics, cost planning (although this definition now means something completely different) and cost control.
1.1.2 Section 2: cost information
The second section is about the different sorts of cost information that are required to undertake an effective study of building costs. These include the traditional sources of cost information such as material prices and measured rates for different kinds of construction work, as well as the more applicable cost analyses. Cost information can also come in many guises such as indices of cost, taxation and sources of funding and design data. While the latter is not strictly cost information, the design of a project has a particular influence on costs and the economics of design are influenced by a large number of factors. The importance of research ends this section. Without research the subject remains sterile and innovation in building costs does not take place. Cost innovation comes from many directions, including designers, constructors and manufacturers.
1.1.3 Section 3: cost practice
The third section is concerned with the practice of cost studies. These use a range of techniques that can be applied to each individual project in turn. A selection of these techniques will be adopted for all projects, depending upon the aims and objectives sought by the client. Even in the simplest case some form of early price estimate will be required, but this on its own is insufficient for modern-day clients. The practices being used are constantly being extended and improved, as Chapter 2 will identify. These include a range of cost and value techniques from the inception through to the in-use phase. The whole aspect of the study of building costs has shifted the emphasis towards value for money, sustainability and ICT integration. This shift has included the following:
- Development appraisal
- Elemental analysis
- Application of cost planning
- Introduction of cost limits and allowances
- Educational research and practice
- Alternative procurement systems
- Costâvalue reductions
- Whole-life costing
- Value engineering
- Facilities management
- Risk analysis
- Economics of sustainability
- ICT in construction
- The future directions of cost studies of buildings.
Some will attempt to argue that a few of these techniques merely limit expenditure and apply a range of cost control practices, i.e. they are restricted to cost-reduction mechanisms. In practice they do much more through refocusing the design and construction teams by adding value to the project. Some other techniques provide the platform for data integration and collaborative working, improving and innovating in the construction processes, where the ethos of the industry is a smart and sustainable built environment.
1.2 The Purpose of Cost Control
The purpose of cost control can be generally identified as follows:
- To limit the clientâs expenditure to within the amount agreed. In simple terms this means that the tender sum and final account should approximately equate with the budget estimate.
- To achieve a balanced design expenditure between the various elements of the buildings.
- To provide the client with a value-for-money project. This will probably necessitate the consideration of a total-cost approach.
- To achieve a balanced cost approach for buildings considering social, economic and environmental impacts.
The client may stipulate the maximum initial cost expenditure, or provide a detailed brief to the design team who will then determine the cost. Most schemes are a combination of these two extremes.
1.4 Cost, Price and Value
The terms cost, price and value will represent different interpretations to different people. Their particular meaning generally lies in the context in which they are being used. It must also be remembered that much of the terminology used in the construction industry has a special interpretation appropriate only to this industry. Cost, to the building contractor, represents all those items included under the heading of his expenditure. His price is the amount charged for the work he carries out, and when this is received it becomes his income. The difference between the two is his profit. Cost is therefore reasonably clearly defined within this context. It relates largely to manufacture, whereas price relates to selling. The term âcost priceâ really means selling at cost. The price, however, that the building contractor charges the building owner for doing the work is to the latter his building costs. The Building Cost Information Service (BCIS) was designed and developed on the basis of the building ownerâs costs. These are in reality the tender price from building contractors. A tender price index therefore attempts to measure the building contractorâs prices (the building ownerâs costs) whereas a building cost index measures the building contractorâs costs. Although there is some relationship between the two, they are not identically correlated.
It is not surprising, therefore, to realise how easy it can be to confuse these two terms if used incorrectly. To adapt the famous quotation, âone personâs [builderâs] price increase is another personâs [building ownerâs] cost increaseâ.
Value is a much more subjective term than either price or cost. In the economic theory of value, an object must be scarce relative to demand to have a value. Where there is an abundance of a particular object and only a limited demand for it, then, using the economic criteria, it has little or no value attributed to it. Value constitutes a measure, therefore, of the relationship between supply and demand. An increase in the value of an object can therefore be obtained through either an increase in demand or a decrease in supply.
Aristotle identified seven classes of value that are still relevant to our modern society. These classifications of value can be summarised as: economic, moral, aesthetic, social, political, religious and judicial. These bear some resemblance to the way in which we identify building life, as shown in Table 17.2. Economic value may be seen as the more objective consideration, since it is measurable in terms of money. The remainder are seen as being more subjective. Maximum value is assumed to be found when a required service or function is attained and when the cost of providing that service or function is at a minimum. Value in this context can be measured objectively, but any solution found through such a procedure risks sub-optimisation. Any increase above the required level of either service or function, for a small extra cost, would often be perceived by clients as better value. A more meaningful approach when applied to the built environment considers the following four components that when aggregated combine to ...