Architecture / June 26, 2018 / .
A project may be completed on time and within budget, but unless it achieves the specified quality or performance criteria it will be considered to be a disappointment or even an outright failure. High profile building failures such as Priory Hall only serve to strengthen the public concern expressed in the Egan Reports findings that 30% of buildings fail to meet the expectations of their owners. Such failures may be prohibitively expensive to rectify, dangerous and can ruin reputations overnight.
This is where a client appoints consultants to produce the design, select the contractor and supervise the work through to completion. The contractor is usually selected on some basis of competition. The traditional procurement route prioritises quality aspects of the project and is also effective in delivering economic designs on most projects. The chief drawback of the approach is the extended project duration due to the need to complete the design prior to tender.
Speedy completion is often required on commercial developments. The pressure to achieve early completion intensifies when financing and interest costs associated with acquiring the site begin to mount. Clients will seek the early appointment of a contractor in these situations to enable a fast start up on site and will favour fast track design approaches where the design is developed in parallel with site construction operations. Such approaches risk allowing insufficient time to identify or consider beneficial design options, and may, on occasion, lead to abortive working and losing time. Speedy construction on site often requires accelerated working and shift or overtime payments, more intense management presence, and the use of dependable subcontractors and suppliers, all of which add to the cost of the project. Fast track approaches rule out cost certainty and the client will become aware of the eventual cost only at an advanced stage of the project.
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.