| Surveying is process which measures the dimension | | | | surveying will ensure that there will not be major |
| of an object that generally present on the surface of | | | | deviations from the planned construction based on the |
| the Earth. The equipment which are used frequently | | | | established reference points and markers. For |
| for surveying includes levels and theodolites. These are | | | | example, the reference points or markers are |
| used for precise or accurate measurement of angles, | | | | established according to an arbitrary coordinates |
| horizontal, vertical and slope distances. With the | | | | system. The continuous monitoring based on the |
| improvement of computer based technology such as | | | | reference points and base lines, the construction |
| electronic distance measurement (EDM), total stations, | | | | surveyor verify the location of structures while |
| Geographic Positioning Systems (GPS) the traditional | | | | construction and do the necessary correction if |
| optical instruments have been replaced. Although, Land | | | | needed.o Preparation of As-Built Plans to ensure that |
| Surveying is common to all types of surveying, there | | | | the construction project or the building project was |
| are noticeable differences between land surveying and | | | | done according to the approved local authority |
| construction surveying. | | | | drawings, specifications and regulations. |
| Land Surveying Vs Construction Surveying | | | | The Construction Surveying needs coordinate System. |
| In many countries, Land Surveying is considered to be | | | | For example, |
| a distinguishable profession. For example, Land | | | | Arbitrary Coordinates based on Geodesic Coordinates |
| Surveyors have their own professional associations | | | | During construction surveying it is common to use |
| and licensing criteria. The licensed land surveyor | | | | arbitrary construction coordinate system. The arbitrary |
| performs boundary surveys and subdivision plans. | | | | coordinate system is derived from the geodesic |
| Whereas construction surveying is generally | | | | coordinates. |
| performed by specialized well trained technicians. | | | | In the case of linear measurements (of roads, buildings) |
| When compared with the land surveyors, the plans | | | | often a chainage or distance will be established from |
| prepared by the construction surveyors do not have | | | | fixed based line such as the center line of the road. |
| legal status. | | | | During construction, the building or other structures will |
| Main features or task under construction surveying are | | | | be located with respect to chainage, offset, elevations, |
| as follows:o Surveying of existing ground conditions of | | | | etc. |
| new construction site. This will cover, topography of | | | | Building Axes are also have to be established in the |
| site, measuring and recording the condition of existing | | | | case of construction of buildings. These axes are |
| buildings and infrastructure. Similarly measuring invert | | | | often fixed along the building column or foundation grids |
| levels and dimensions of sewers and manholes that | | | | or major load bearing walls. |
| comes underground infrastructure.o Setting-out or | | | | Reference Lines |
| layout of proposed building site, and building location. | | | | In construction or building projects an arbitrary |
| Fixing of datums or reference or control points that will | | | | reference lines may be established either north-south |
| guide the construction of new structures such building, | | | | or east-west directions. It may not necessarily be |
| roads, canals and sewers, etc. Also, the construction | | | | based on true coordinates. |