Senteck News
Catching Roof Overload Early Averts Trouble
by Lurie Silberg
Is there anyone who hasn't heard of NIMBY, the acronym that stands for "Not in My Backyard?" Probably not. But what about the acronym NOMR? Not exactly a household word.
Maybe it should be, though. Perhaps NOMR, or "Not On My Roof," could become a familiar acronym in the shopping center industry.
Each year, catastrophic roof collapses cause multimillion dollar losses for both business owners and insurance carriers. The losses come in the form of claims for personal injury, property damage and long-term business interruption. As for the dollar losses, a roof collapse can be extremely costly.
But the general belief among building owners is that a roof collapse isn't something they'll ever have to deal with a sort of "that can't happen on my roof" mentality.
Yet roof collapse, whether caused by snow and ice buildup or structural problems, can prove costly in dollars and in lives.
Typically, roof maintenance for commercial properties consists of performing periodic roof inspections, repairing leaks and planning for replacements. In spite of these precautions, some roofs will collapse anyway.
One company, SafeRoof Systems, has come up with a new approach to the problem. Based in Mattapoisett, Mass., SafeRoof has developed a sort of smoke alarm for roof overloading. The DMD1000 system is a patented laser-based technology that is designed to help prevent roof collapse by warning building owners of an impending overload in advance.
SafeRoof produces and installs the device, which uses a series of lasers and optical targets to detect excessive structural roof loading. The system acts as a very early warning system that alerts the owner when (and where) a roof is holding 60% to 70% of load capacity.
SafeRoof executives see a real need for its products in shopping center developments below the Mason-Dixon line, according to Bill Korensky, director of quality assurance for SafeRoof. That geographical area underwent a tremendous commercial real estate boom in the 1960s and '70s, especially in retail centers, he explained.
But building codes on the state and local level change with the years, based on weather patterns. Older buildings, however, often don't change. When buildings change hands, new owners often inherit unknown structural problems. People just don't know enough about the property they lease, said Korensky, "and you can't predict the weather as well as you used to be able to."
Furthering the problem, shopping centers have seen tremendous resale and consolidation over the years, "so we foresee malls and big box retailers as a primary customer," he said.
"[Owners] may not know what they are getting. They wouldn't necessarily know what load their true capacities were, especially in an older building," which may have been modified to include air conditioning, he explained.
Roofs may have been built, for example, for loads of 40 pounds per square foot, in places where the codes have changed to 60 pounds. People may also have started adding layers to their roofing, and adding new materials, according to Korensky, who stressed that roofs may be within 10 and 15 pounds per square foot of collapsing, and owners don't even know it.
Korensky acknowledges that the great majority of buildings out there are safe, but it's the 10% that are not that concerns him.
To get the attention of that group, the company is targeting facility owners and managers, risk managers and insurance companies.
George Smith, materials section manager in the approval division of Factory Mutual Research Co., said roof collapse is a much bigger issue than people realize. Shopping centers, as well as many types of commercial properties, are especially vulnerable for a variety of reasons. "Many shopping centers are [made from] pre-engineered metal buildings that have been designed to certain specs and then sent to a factory where it's all produced, and then shipped to the job site."
This type of pre-engineering is very common to malls, which are built rapidly, Smith said. The bottom line is that the "design criteria doesn't take into account collapse."
Roof collapse can be a problem if safeguards have not been built into the design, Smith said. "Obviously, the best thing to do is to build the building more substantially, but if that hasn't happened," Smith suggested, "a product like SafeRoof's could be very important."
Norwood, Mass.-based Factory Mutual Research is the research and testing arm of three major industrial and commercial property insurers: Allendale Insurance, Arkwright and Protection Mutual Insurance, all insurers of commercial properties. As part of its research function, Factory Mutual tests and either approves or disapproves loss-prevention products and technologies for use by these companies. The DMD1000, which was invented by Jeff Canty, the president of SafeRoof, and patented in 1996, has been approved by Factory Mutual.
"Building owners may think the investment isn't worth it because it's going to cost a dollar or two more per square foot. But they need not see that in the long run, they might not be able to afford not doing it," Smith said.
SafeRoof costs 50 cents per square foot, according to Korensky, who noted the typical cost of a sprinkler system is about $1 per square foot to $1.25 per square foot.
Hard data on roof collapses is hard to come by. According to Korensky, there have been about 1,000 roof collapses in the United States over the years, including both residential and commercial properties.
Mary Brighner, national director of education for public entities, health and nonprofit agencies for risk management and loss prevention specialist Arkwright, is a big proponent of SafeRoof. She is working vehemently to get the system installed in public schools "as a proactive measure to safety."
Brighner said it's not worth waiting for lives to be taken.
To date, SafeRoof has installed two systems, one in a Showcase Cinema in Manchester, Conn., and one in a high-rise building owned by the Fortress Co. in Boston.
Officials for Showcase Cinemas, which is owned by National Amusements Co. of Dedham, Mass., believe SafeRoof has already saved the company a lot of money.
The device helped avert disaster on two occasions, said Eliot Finn, senior project manager for the Manchester Showcase Cinema. "This past January, a heavy mix of snow and rain was followed by freezing temperatures. The net result was predictable and falls into the category of what building owners fear the most. The downspouts froze, the building was full of ice and then came the rain. The on-site manager was notified by the system and was able to take quick action in getting a roofer to pump the water off the roof," Finn said.
"Building owners may think the investment isn't worth it...But they need to see that in the long run, they might not be able to afford not doing it."
- George Smith, materials section manager, Factory Mutual Research Co.
SafeRoof saved Showcase more than $1 million, according to Patrick Watson-Hogan, a risk manager for Old Colony Construction Corp., which builds shopping centers. "Had Showcase lost that roof over the main electric room, there would have been over $1,000,000 in damage not including the fact that the cinema would have been down for at least eight to 10 weeks."
More importantly, however, Watson-Hogan said he believes the SafeRoof system helped save lives at Showcase, which first installed the system in September 1998.
Showcase, which operates 115 theaters in enclosed regional malls, strip centers and as freestanding theaters, said it would begin installing the system in all its cinemas.
In general, the approach to roofing troubles has been "more reactive than proactive," according to Jim Russo, president of Boston-based Case-Lea, an engineering company that does a lot of work with rehabilitated structures. Russo, who said Case-Lea works closely with many retailers, including Bradlees and Stop & Shop, said roofing is a very important issue. "It's a life-safety issue, but it unfortunately ends up coming down to dollars and cents for those who make the roof decisions."
The instances of roof collapse are actually very low, meaning a product like SafeRoof could have a hard time carving a niche. Case-Lea, which is very much behind the product, believes a break at the insurance end would give property owners an incentive to install the device.
Russo said the standard answer of retailers and mall owners has been that they don't want to spend the money. Until someone tells them to, that's likely to remain an issue, according to Russo.
He agreed that in some cases, companies that buy existing malls don't know what they are in for. "The former owner doesn't have to disclose prior roof problems," explained Russo.
"There is always a potential for problems with flat roofs," said John Richley, director of operations for mall developer The Cafaro Co., Youngstown, Ohio.
Most rain-loading collapses occur on flat roofs with slopes of 1% or less, on roofs of lightweight construction, or on roofs that were designed for minimum live loads, according to Factory Mutual.
The Cafaro Co.'s policy, according to Richley, is to police its roofs closely. "We require anyone who needs access to the roof to check in. Beyond people damage, weather in general plays a significant role. So there is constant vigilance at the local level."
The guiding factors for owners are the insurance companies and the codes, said J. William Ralston, architectural coordinator for the Taubman Co., which operates regional malls across the United States. Both address wind pressures, live loads (water, snow, wind and people) and dead load (the weight of materials).
Ralston, who said he hadn't heard of the product, agreed that a fail-safe system warning against potential disaster could be warranted in areas where weather could be a contributing factor to roof collapse. "In a place such as Detroit where there are freak snowstorms and you have a choice, where someone has to make a judgement," it could be warranted, he said.
Otherwise, "it's been a minor problem and we don't anticipate problems in the future," Ralston said. "In snowbelts, systems like this depending on the cost could be a consideration." But "we've never had a roof collapse."
Reprinted with permission from Shopping Centers Today Magazine
