Requirements of preliminary and detailed estimate:

To prepare a preliminary estimate, quantity of work to be planned is measured in terms of unit of person, built up area, extent of work in kilometer such as a preliminary estimate of housing can be calculated based on type of house and number of house to be built. Similar preliminary estimate of highway can be calculated by knowing the type of road in terms of lane or pavement and length of the load.

Preliminary Estimate

Different methods of preliminary estimate can be grouped into the following categories –

• Time referenced cost estimate


• Cost capacity factor


• Component ration/installation cost ratio


• Parameter cost

The preliminary estimate is obtained during early phases of project. As the project progresses, an estimate keeps on getting refined and lastly we get definitive estimate.