Architecture / June 23, 2018 / .
Many construction projects involve the design and construction of a building which is tailored to meet the clients specific requirements. No two construction projects are identical - there is no such thing as the average building project. The cost of the building will depend on its particular characteristics and these are largely determined by the architect. The design options are almost limitless and the resulting costs can be difficult to forecast reliably in many cases. On the other hand, certain types of buildings such as schools have well established cost histories and are usually subject to a cost limit.
The geometry of a building has a major impact on costs. Building morphology is concerned with the size, shape and complexity of the building. This section provides a very brief outline of the principle morphological factors which influence the cost of building work. The reader is referred to the numerous publications which examine this topic in greater detail. The main design factors which impact on cost are: plan shape, size of building, wall to floor ratio degree of circulation space, storey heights total height of the building grouping of buildings.
This is where the contractor works alongside or within the design team providing a construction management service. The management contractor does not undertake either the design or the direct construction work. The physical construction is carried out by specialist subcontractors, package contractors. There are two main forms of this approach: Management Contracting where the contractor employs the subcontractors and Construction Management where the subcontractors are employed directly by the client and the project is managed by the construction manager - there is no actual main contractor. Management procurement routes are associated with fast moving, complex construction projects. The early appointment of manager within the design team allows the design and construction operations to be fast-tracked while also ensuring that the required quality standards are delivered. These projects, however, tend to be expensive. Figure 1 sets out a summary of the advantages and disadvantage of various procurement approaches which may be of use in meeting project objectives.
The factors influencing this decision include: Is the more expensive option a worthwhile investment? If it can be demonstrated that savings will arise as a consequence of incorporating the more expensive alternative, then the client is well advised to choose this option. The quicker the payback period, the more likely it is that the more expensive option will be chosen. How flexible is the client‟s budget to finance more robust, better quality or more economic structures or systems? Regardless of whether the client wants the more expensive alternative he or she may not be able to afford it. Retrofitting, however, is inconvenient, disruptive and much more expensive subsequently. Will the client occupy the building? Clients who develop to sell or lease may be less concerned with the operating and maintenance costs of the facility which will be passed onto the eventual purchaser or user of the facility. Clients who spend more initially will seek to recover their investment through higher rents or sales price. This approach may be adopted by future oriented private sector clients concerned with sustainability and green building issues. What is the life-span of the building? The shorter the planned life span of the building the less appropriate it is to incorporate robust and durable materials and systems.