Approximate estimation (fast estimation):
The approximate estimation is prepared before laying the final designs & specification and general specification of the project.
The purpose of approximate estimation is:
- Determine the cost of the structure quickly.
- Make a comparison between several alternatives.
- Checking the final cost of the structure which determined by detailed estimation.
Method of used for approximate estimation:
- Floor – Area method. (Price of one square meter of building).
Use to determine the cost of the following building:
(Offices, Schools, Houses, Apartments, Hospitals …..Etc.) .
It is the best method for determining the cost of the new building , depending on the results getting from old buildings ( buildingsbuiltbefore ).
For the multi-story building there are two assumptions :
- The cost of all floors with in basement and roof are in equal costs for one meter square.
- The cost of the basement is (60%) and roof is (40%) of the other floors.
- Cubic method , (volumetric method )
This method is more accurate than the floor-area method.
For multi-story buildings apply the following assumptions:
- All floors are in equal costs for one cubic meter.
- The cost of the basement is (60%) of the cost of the other floors.
The volume of the floor is calculated as: Volume=Area ×Height of one floor
The height of one floor is determined as follows:
- Ground floor: the height is from top of the footing to half of the parapet.
- First floor: the height is from top of ground roof to half of the parapet.
- For other floors: the height is from floor to floor.