Architecture / June 17, 2018 / .
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.
The payment arrangements adopted on a contract directly affects the level of risk borne by the contractor. Where the contract is let on the basis of a drawings and specification lump sum the contractor assumes the risk for both the quantity and pricing. In lump sum contacts based on bills of quantities and remeasurement contracts the contractor assumes the risk for the pricing only. With reimbursement contracts the client assumes the risk for the quantity and pricing. The payment arrangement, therefore, directly motivates the contractors efforts to carry out the work in an efficient and economic manner. This in turn has a major impact on the final price paid by the client.
The quality of the building will express the clients ambitions for a prestigious development. This may range from a top quality building with minimal maintenance requirements where all matters relating to the design are controlled by the design team to developments such as retail or industrial process where the detailed design is not critical and can be undertaken by the contractor. It may be essential to use high quality materials in conservation projects or where planning conditions have been imposed. High standards of craftsmanship will also be required on alterations and extensions to listed or historic buildings.
The site topography i.e. the natural site features, ground conditions and obstructions, existing and adjoining building, and underground and over-ground services all impact on how the building is designed and subsequently constructed. The nature of each site must be individually checked to establish potential problems. Greenfield developments cost less than brownfield sites which may incur significant demolition, site clearance and remediation costs. Heavily sloped sites require extensive stepping or cut and fill operations and such sites may be dangerous and adversely affect the working conditions and productivity of operatives and plant output. Sites with poor loadbearing capacity will require more expensive foundations while exposed or waterlogged sites will also reduce overall productivity. The cost of dealing with unforeseen ground conditions, archaeological finds and encountering uncharted buried services may be substantial and will be borne by either the client or contractor, depending on the form of contract employed.