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Unseen Danger! When Roof Damage Goes Undetected Because of No Leak

Steven M. Thomas in Building Operations on March 2, 2012

New York City

March 2, 2012
  • Concrete decks tend to not let water migrate into the interior of the building.
  • Sub-surface insulation boards can absorb large quantities of water and may never leak into the interior.
  • Lightweight concrete is very absorbent and can greatly reduce noticeable leakage into the interior.

Here is an alarming true story: In a 13-building condominium complex at which I worked on a recent insurance claim, no one reported any leaks after a hurricane had impacted the property a few years earlier. However, a wise property manager and the board president sent maintenance personnel to do a cursory inspection of the roof to see if any damage was visible. The maintenance people reported that other than drains being clogged on every roof, none of the roofs appeared to have been uplifted. They did report that over a foot of water was present on each roof but one — the only building in the complex that had a walk-out stairwell to the roof, which acted as an overflow for ponding water.

The condo association filed an insurance claim for the damage and asked the insurance adjuster to look at the roofs. The adjuster did report that he observed several scrapes and gouges to the roof membrane on each of the buildings, but it was his position that the roof damage he observed was not over the deductible.

Insurance Outrageous

The property manager and the condo-board president, wanting a second opinion, hired a public adjuster to assist them in the claims process and a roofing consultant to evaluate the condition of the roofs. The consultant performed nuclear moisture surveys on each building and found that 12 of the 13 roofs were saturated. The insurance company did not believe the consultant's results and hired a separate company to perform another survey on three of the buildings in an effort to refute the consultant's conclusions.
That company performed an infrared moisture survey. However, the buildings had been re-roofed just two years prior to the storm event, with smooth-surfaced silver reflective coating and six inches of lightweight concrete. An infrared survey isn't recommended for this type of roofing assembly by the American Society for Testing and Materials (ASTM) and others, and the company found its results inconclusive. So, the insurance-company adjuster, believing he had fulfilled his duties to report he found no damages over the deductible, denied the claim.

The insurance company hired a

separate consultant to perform

another survey to try to refute the

condo's consultant's conclusions.

The board was then forced to hire an attorney. The attorney subsequently hired my firm. After reviewing all the previous tests performed on the roof, we performed our own testing, which included a nuclear moisture survey, gravimetric core analyses, and wind-uplift and fastener-uplift testing.

Our moisture survey determined that the roofs on 12 of the 13 buildings were indeed saturated, as the board's consultant had found three years earlier. (Wet insulation does not dry out.) The wind-uplift testing found that the saturation of the lightweight concrete severely diminished the roofing system's uplift capabilities. Likewise, the fastener-uplift test of the lightweight concrete found that the concrete could no longer provide the minimum resistance values for fasteners. Finally, the gravimetric core analysis determined exact moisture contents.

From this testing, we proved without a doubt that the lightweight concrete was damaged beyond repair and had to be completely removed prior to a new roofing system being installed. We were also able to pinpoint causation for how the moisture entered the roof during the hurricane. It was not that difficult to figure out.

The insurance adjuster and his company's experts hung their hat on the belief that if a roof is not leaking then it can't be damaged. They overlooked obvious signs of moisture infiltration into the roofing system and did not believe the first set of roof-moisture surveys performed by a certified testing company. In fact, the insurance-company experts attempted to refute the first set of moisture surveys by cutting one core on one building to determine that all of the first moisture surveys were incorrect. The sad part is that the insurance company believed them.

What Finally Made the Insurer Pay Up

Even when my firm provided another certified moisture survey, the insurer was skeptical. The first testing company and my firm are certified testing companies; however the carrier's expert insisted on having another company perform another nuclear moisture survey. And even though this firm was not a certified testing company, they came up with the same results as we did. The insurance company eventually paid a claim of over $5 million. Had the company's experts been more diligent and followed accepted procedures for evaluating roofs, the case would have been settled much sooner.
If your co-op or condo building has been in the path of a hurricane, a major storm or a severe straight-line wind event, have your roof inspected by qualified independent personnel. Insist on scientific testing to back up any opinions from either the insurance carrier or your own engineering or roof consulting firm.
Most importantly, do not accept visual observation reports. Failure to accurately evaluate damage could lead to further damage to the property. Never assume that because a roof does not leak, it was not damaged.


Steven M. Thomas is president of the Florida-based certified testing laboratory Roof Leak Detection Company, founded in 1981. This is adapted from his post at the website

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