At the beginning of any project, the question arises: what will be the total costs? The private client pays what he can afford; the public client calculates the parameters for a building on a comparative basis. When there is no great difference between the estimated sum and the expectations of the client, one will begin to define in greater detail the architectural goals that can be achieved with the funds available. Cost pressures can lead to new architectural solutions and typologies as well as helping to concentrate the architecture on essentials. An overemphasis on economies, however, can mean that one goes beyond architecturally defensible boundaries, with the result that the magic triangle of quality, costs and deadlines falls apart – at the expense of quality (ill. a).
Cost planning is not a closed book. An understanding of this discipline in Germany, for example, is based on German standards. In other countries, it may be practised by an independent profession. The principles of this discipline are a selective view of construction in which a building is broken down into its individual elements (ill. b). These can be analysed at the preliminary planning stage to obtain an initial estimate of costs. With increasing degrees of detail in the planning, the elements will become more concrete and the process more accurate. Cost values based on floor area and volume are not sufficiently precise and can ultimately serve merely as a check. (Collections of data like those of the BKI1, RBK1 or Plakoda1 can be employed to corroborate calculations.) Figures based on previous projects also contain a potential for error, especially if current developments are not taken into account, or if new types of technology are involved in a scheme.
If the stipulated budget and the calculated costs differ, a cost-adjustment process will be necessary, the aim of which is to achieve the maximum architectural quality for a given sum of money. Two possible forms of adjustment exist: a reduction of the estimated costs – as long as it is still possible to implement the architectural goals; or an increase in the budget. The latter is the simpler, more comfortable alternative, but also the less common one. Cost reductions mean investing the available money in really essential constructional elements and saving on less important parts. A constant consideration of alternative forms and materials is helpful in this respect.
Once the actual goals of a project have been defined, a basis is established for determining the project costs. One cannot build a school for the same price as a warehouse, however. The budget and the task in hand must be matched. An inadequate definition of the planning goal is not uncommon and leads to additional work or changes that are likely to increase costs. Regional building traditions and local circumstances can also be the cause of cost differences. Not all forms of construction are equally represented in every region, and importing alien technology can result in unsuspected problems. On the other hand, regional wage differences mean that mobile finishing trades can often travel long distances without incurring additional costs.
In many cases, local peculiarities are not taken into account in calculating the costs of a building. The most commonly underesti-mated part of a structure is the foundations – often because an investigation of soil conditions is undertaken at too late a stage. Nothing is more annoying, however, than having to invest large sums of money in the substructure that will then no longer be available for the visible sections of the building above ground. A further cost factor is the accessibility of the site (ill. c).
Simple design concepts are not inexpensive per se, although they do have a greater potential for cost-effectiveness. Well-ordered structures based on a single, dominant idea with a clear spatial organization and a compact form can smooth the path to good architecture at a reasonable cost. A popular control instrument is data relating to the area and volume of a building. Figures based on the floor area have a greater relevance, however. Decreasing the volume merely leads to a reduction of the wall heights with an appreciable loss of space, which will have a decisive effect on lighting, air and atmosphere.
A succinct design idea accommodated in a clear building form will help to achieve a low-cost load-bearing structure. Limiting the material and colour concept to a central architectural idea also serves to reduce unnecessary variations in the design. The specification of materials and surface properties is of course, a major cost factor. Exposed concrete, for example, can be a bottomless pit, and the outcome may nevertheless be disappointing. Carefully laid exposed brick- or blockwork, on the other hand, can cost less than a rendered wall (ill. e). Anodized aluminium is not significantly more expensive than powder-coated forms, yet it is much more elegant (ill. d).
Prefabrication is not automatically a sound choice: either one should opt for products that have proved successful, or one should develop simple system solutions using common materials that can be quickly and economically put together by craftsmen of average ability (ill. f). In the case of mechanical services, it is important to ensure a state of transparency. Cost effectiveness in this sector depends on the architect keeping abreast of cost-benefit analyses. Even economic forms of construction may lead to considerable expenditure for services.
Responsibility for the construction work can either be placed in the hands of a general contractor, or one can enter into separate contracts with individual trade companies. There are arguments in favour of both methods. In the former case, the general contractor will coordinate the entire work on site, but he will calculate a surcharge on all building work and services.
Clear, detailed bills of quantities (as required by VOB 2,3 regulations in Germany) are essential for cost-effective construction if one wants to avoid additional sums in a tender to cover unknown risks or subsequent claims for unforeseen work. Foresight in questions of quality control can prevent extra costs arising in subsequent works on site; and a constant process of cost control can help to avoid having to make reductions in quality at the finishings stage in order to compensate for unexpected cost increases earlier. Prefabrication is also an issue on site, where it can help to decrease costs by leading to a reduction in the duration of scaffolding (ill. g), for example.
“What doesn’t fit will be made to fit” might be a valid concept in cost-conscious building, but that will depend on who makes what fit. Responsibility for costs should lie solely with the architect. Only the person in control of costs can channel money to the proper places. The common practice of leaving the overall costs to a project manager leads to a lack of transparency and is ultimately a hindrance to good architecture. In this field, architects have an opportunity to take the entire planning process into their hands again and to create good design at a reasonable cost.
