As architects involved with forensic work for many years, we have used the same diagnostic tools. These tools have, on many occasions, proven inadequate for the complex issues or even the geometry of todays architecture.
Often times the forensic work is conducted as part of identifying construction defects. Construction defect lawsuits on historic buildings typically arise from a conversion that involves adaptive reuse of the historic structure; for example, converting a historic warehouse to multi-family housing (condominiums or apartments).
As with any construction defect case, the opposing sides retain experts to conduct a forensic investigation and submit findings for discussion in hopes of coming to an agreement during some form of mediation or arbitration to avoid very costly trial proceedings.
In this article I will discuss the use of 3D data in conflict resolution through a couple of case studies involving historic masonry structures.
Surveying masonry typically involves a macro level survey that identifies large cracks and other readily observable defects. It also involves micro or localized surveying that is conducted up close in small areas for condition documentation of mortar joints of brick or stone exfoliation, etc.
Disputes between opposing forensic teams typically involves connecting the micro surveying of localized areas with the macro surveying of the overall facade.
Four years ago when I start the wide use of laser scanning on design work, I was involved in one such dispute. A historic structure from the 1880s that had been converted to condominiums, while retaining the original historic shell, had severe deterioration of the brick masonry, which was not restored during construction. Three years had passed since the field investigation was completed with no agreement between the defense expert and me. The disagreement was related to the scope of deterioration of the original brick masonry walls/shell which directly related to connecting multiple surveys together. A considerable amount of money was spent by both sides of the dispute without achieving an agreement.
While field laser scanning work was in progress on one of my large scale design project two blocks away, I was able to get the scanning crew to spend half a day and scan the main facade of the historic masonry building. Our service provider developed deviation maps clearly showing the degradation of the mortar across the entire elevation. Additionally we discovered previously unknown deformations (out of plane) caused by earthquakes.
Once we presented the data obtained by scanning, a settlement agreement was reached and we were able to move forward with restoration work.
On the next historic masonry building involving construction defect litigation, we scanned the building envelop prior to starting the field investigation. Data was presented to the opposing side very early on in the mediation process and agreement on the scope of repair of the masonry was reached shortly thereafter.
Comparing the process we went through on the two projects, the first we scanned after three years from the start of the forensic work while the second was scanned very early on in the process with very contrasting results. The early collection of 3D data on the masonry resulted in saving many months of discussions and disagreement over less reliable data collected with antiquated means. When one adds the associated expense of experts and lawyers time and the damage incurred to building components, it is easily in the tens of thousands of dollars. The data was also used during litigation on these projects to obtain very accurate cost estimates for repairing the defects.
The use of scanning in forensic architectural work extends much beyond historic masonry structures. I have recently used it in identifying and documenting improper drainage on large podium slabs. It is clear to me that the use of 3D scan data in forensic architectural work will change the approach to conflict resolution by speeding up the process and making it much easier to bring about a meeting of the minds.