There are different types of construction cost estimation done by owner, contractor and engineer. They all have their own purpose to know in advance the expected cost of the undertaking in varying degree of accuracy, at different phases of construction.
Comparison of Contractor ‘ s and Engineer ‘ s Estimator
Construction cost Estimation
Following are the different types of construction cost estimation:
Each phase of a project life cycle requires a different type of estimate–each estimate requires different types of information.
Advantages of Preliminary Estimates
Purpose of Preliminary Estimates:
Unit prices are obtained from data on projects already performed. Cost of labor, substance, and machinery for all units of work are added together and divided by the number of units involved.
Uses of Cost Indices
To update old cost information to current date
Cost of new facility = cost of old facility x (new cost index/old cost index)
To predict future cost
i = predicted rate of cost escalation per period
n = number of periods (years)
As the quantity built increases, the unit cost decreases,
Size Factor = (Proposed Size / Comparison Size)
UCM = Unit Cost Multiplier
Hard to quantify but must be evaluated