One of the primary drivers for the rapid growth of high-definition surveys in construction is the fact that contractors place a high value on services that can significantly reduce risk to their construction budgets and schedules. High-definition surveys have proven over time to sport three advantages over traditional methods that can provide valuable risk reduction benefits for cost- and schedule conscious project managers. These construction risk-reducing advantages are:

• Higher level of completeness
• Better accuracy
• Quicker availability of as-built data

For complex structural projects, scanning's higher level of completeness translates into less construction risk in the area of "construction interferences." Construction interference is a case where a structure, such as piping or steel framework, is in the process of being installed and the contractor makes an ugly discovery that the planned layout physically clashes with existing structures. The enormous amount of data collected in a scan can accurately identify objects as small as a nut or bolt.
Secondly, for many projects, the higher overall accuracy of a high-definition survey translates into less risk of "fit-up" problems. A fit-up problem is one in which during an installation, the contractor makes the unpleasant discovery that some element does not quite fit-up exactly with another element for which it was intended. While some minor problems can be adjusted in the field, others may lead to expensive rework and additional material shipping costs. The contractor then has to fight for the change orders to cover the additional cost. With scanning all of these potential problems can be identified up front, which ensures a smoother running project.

Finally, most projects start up behind schedule. Quicker availability of as-built data helps to alleviate some of that pressure, not just through minimizing field re-visits, but through easy integration to AutoCAD or Microstation drawings and geo-referencing to on-site survey control. Laser scanning reduces missed measurements and the need to visit the site over and over by producing a more complete picture of the real world environment. Likewise, the collected data can easily be overlaid on existing drawings and oriented to existing survey control on-site. The savings in time alone pays for the cost of the service.

Benefits:

• Identify problems with the design before the time comes to build
• Avoid costly fitting problems with expensive items such as elevators or conveyors
• Quality Assurance that subcontractors are building as per drawings and specs
• Protection from litigation through scanning documentation that cannot be tampered with