As-built surveys are prepared most often at the end of construction to satisfy municipal or lender requirements. They help to determine that all improvements on a site were constructed in compliance with the specifications as outlined by the engineer during the design process. An as-built survey is often necessary to obtain a certificate of occupancy from a city or county. This survey usually reflects all building, curb, parking lot features, utilities, sanitary sewer, storm drainage facilities, and other structures as needed.

As a development project and its construction progress, the work scope often changes. Items are moved, added or removed from what was originally planned. Beyond executing the change in the field, changes need to be documented to show what was actually constructed. Hence, the owner usually requires a final record to show all changes or, more specifically, any change that modifies the tangible portions of the completed work. The end product of this effort is what we call as-built drawings. These as-built records, becomes more important, as we continue to build on top of old work, land ownership changes, or for public works.

These factors often make it necessary, or at least a good source of verification, to have a separate firm conduct field surveys to obtain existing conditions documentation, or, as-builts.