June 6, 2019 | Vaughn J. Mantor
Nashville, Tennessee is booming. Growth and opportunity bring more people to town, about 100 per day, and the city needs more classrooms. Just one school is undergoing an $88 million renovation and addition.
The pressures of such growth have given contractors an unusual opportunity, and many have taken it. Many contractors are declining to bid on projects unless accurate, as-built documents are available beforehand. As one might expect of a city founded in 1779, school buildings are often old and without accurate, measured drawings. Here’s an example from one of the school’s archive:
How did this come to pass? How did contractors come to this level of influence?
Without an accurate set of drawings, contractors must adjust their bids to protect against uncertainty. They may plan to buy more material; they may take their own measurements, at their own expense; they may plan for a longer time on site; they may plan for more RFIs*; they may plan for more unproductive time. All these considerations, among others, increase the cost to the contractors and the price to their customers.
In Nashville, the boom has filled the schedules of many contractors. So which would you choose? A project fraught with uncertainties and potential problems and losses? Or one with a guaranteed set of measured, accurate drawings of the building undergoing remodeling? Compare the image above with this one from the laser scanning data, annotated with construction specifications.
Many contractors are making the obvious choice, and projects without accurate drawings go wanting.
Capital Project Solutions of Nashville (CPS) understood the value of laser scanning for the Head Start schools that were scheduled for improvements because the technology would help METRO Nashville’s** ability to write and bid out accurate scopes of work. CPS was excited to use DWP Live and Verify 3D to provide laser scanning services and to create the laser-accurate drawings.
According to Michael Martin, Project Manager for Capital Project Solutions, “On the MAC Head Start projects, the [CAD] file deliverables were an essential tool in bridging the gap between managing older facility assets without accurate information and being able to create biddable scopes of work with enough accuracy to attract quality bidders.” See the end of this article for a list of the data that Verify 3D delivered.
In Nashville, as of publication date, we have scanned four schools:
North Head Start
Tom Joy Head Start
Berry Head Start
Richland Head Start
Contractors were not the only ones to benefit from the scanning. Everybody did. And these results are common in our experience.
Architectural design goes faster with an accurate CAD model as the starting point. This is especially important when the building in question has historic qualities.
Engineering design benefits in the same way. Maybe more so. For example, the engineering of ventilation and air conditioning is particularly sensitive to twists or turns in the ductwork.
The accurate drawings will attract high-quality contractors submitting accurate bids. The better contractors have learned how to make the most of available information. (And we will address this important point in another article.)
Fewer RFIs will make life easier for the general contractor, among others. On a typical project of $5,000,000, RFIs cost $100,000. The laser scanning data reduces both the number of valid RFIs and the number of those filed unscrupulously. For the school mentioned in the first paragraph above, that’s a likely additional cost of $1,780,000 sans laser scanning and modeling.
The shortened schedule means the cost of construction to the city is reduced.
Disruption to the students and the schools’ schedules will be minimized. Bidding specifications demand construction schedules fit into the schools’ schedules.
The schools will have a current and accurate set of drawings for asset management, which will enable better maintenance of the facilities.
And, ultimately, the lower cost saves the taxpayers’ money.
Nashville’s experience with 3-dimensional laser scanning illustrates a characteristic of technology in general. From time to time, a technological innovation radically changes an entire industry. We believe laser scanning and modeling benefit every project as long as the technology is properly applied.
If you’d like a personal explanation or demonstration of the ways laser scanning can help you, our contact information is directly below.
Because our experience in this technology dates back to 2002, Verify 3D knows the most appropriate equipment to use on each project and how to use it for the best benefit to our clients. For this project we used a Leica laser scanner, a P-30, and Leica Cyclone software for registration. Per contract, Verify 3D delivered ReCap point clouds, TruViews, and a 3D Revit model, 2D floor plans, reflected ceiling plans, and external elevations. Most of the delivered 3D model was created at Level of Development (LOD) 200.
*RFI – Request For Information. A formal process for resolving construction conflicts and uncertainties.
**Metro Nashville – Metro Nashville General Services.