TABLE OF CONTENTS Colman J. Mullin
Senior Estimator
Bechtel Corporation
San Francisco, California
Black magic. Bean counting. Guess work. Guestimates. Ask a group of engineers to describe construction cost estimating and that is what you are likely to hear. Not that they regard cost estimating as unimportant. They realize it is essential to all projects. But from their point of view, it is a mysterious process.
There is nothing esoteric, however, about cost estimating. It is an engineering discipline like any other, with its own rules and techniques, and a knowledge of these can be very helpful to those in other disciplines. Such knowledge can, for example, help designers, contractors, and building owners to determine whether an estimate adequately reflects their intentions and to understand how a change in design or construction can affect the schedule or total cost of a project. This can lead to consideration of appropriate alternatives and development of better quality, lower-cost projects.
The total price of a construction project is the sum of direct costs, contingency costs, and margin.
Direct costs are the labor, material, and equipment costs of project construction. For example, the direct cost of a foundation of a building includes the following: the course of the project and affect overall project cost. Although the effects and probability of occurrence of each contingency event cannot be accurately predicted, the total effect of all contingencies on project cost can be estimated with acceptable accuracy.
Costs of formwork, reinforcing steel,...
