Architecture / January 13, 2018 / .
The issue of the cost of construction work is one that is rarely far from the minds of construction clients, design teams, constructors and, of course, quantity surveyors. The cost of constructing a building project is a primary concern for the vast majority of construction clients. Indeed one of the most common initial questions a client has is. What is it going to cost me? often followed closely by. can we do it any cheaper? Providing answers to such questions is a key objective of quantity surveyors, whose task it is to predict the likely cost of building work and to manage the evolving project design to ensure that the clients approved budget is not exceeded. This is a challenging task, which frequently involves one-off, unique, purpose made buildings, and the QS typically operates within a design team brought together specifically for that particular project.
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.
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.
It is clear that the purpose of a building will have a major bearing on its cost. Housing has a very different cost range to apartments and commercial development. Likewish the cost of providing public amenities such as conference centres, theatres and sports stadia cannot be directly related to the provision of public infrastructure such as hospitals or schools. The cost of each building must be related to its individual design, which may be benchmarked against similar national and international projects.