November 18, 2004

Waterlogged walls? New system will tell you

  • Water detection technology, borrowed from the cable industry, serves as an early warning system to head off mold problems.
    Special to the Journal

    Detec moisture detection system
    Photo courtesy Detec Systems
    The Detec moisture detection system uses copper tape to sense water intrusion on the building envelope. Tape is installed when walls are open during construction or remodeling.

    Think of it as "Big Brother" of the building industry.

    A new water intrusion detection system uses a combination of copper tape, remote sensors, low-voltage wiring and high-speed cable connections to monitor moisture in a building and alert the owner long before mold has a chance to take hold.

    The product, developed by Detec Systems of Conover, N.C., and Sidney, British Columbia, is entering the Pacific Northwest market at the 93-unit Reverie condominiums; the first phase of the mixed-use Marcato development in downtown Tacoma.

    "There's a liability exposure that's out there," said Michael Weinstein, a partner with Vision One LLC of Seattle, Marcato's developer. He is well aware of water intrusion problems that have resulted in messy lawsuits and costly claims for other condo developers throughout the mold-prone Pacific Northwest, and made the decision to use Detec in the Reverie. "We've had no problems, but we don't want them."

    The system uses a three-tier model of detection, evaluation and notification. A moisture-detection tape with flat copper conductors and stainless steel probes is installed during construction or renovation. The tape is placed at critical locations within the building envelope — windows, vent hoods and roof flashings — where water penetration is possible.

    The tape, which remains hidden within the walls and ceilings and underneath floor coverings, is connected by low-voltage wiring to a remote zone sensor that communicates with a main computer residing in the building.

    When water leaks occur, the moisture probes trigger an alert to the building's central computer system, which in turn transmits the information to a 24-hour Detec monitoring center in Canada. The date, time and location of the moisture is tracked, and analysts at the monitoring center reference the data with current weather conditions and the building's as-built plans to pinpoint the exact point of moisture intrusion.

    Analysts then alert the building owner of the problem via phone, email or page; allowing for the owner to arrange for the leak to be fixed long before water has a chance to cause serious structural damage.

    "Moisture in walls is silent," said Duncan Townsend, Detec Systems executive vice-president. "No one knows it's there until you see mold on your drywall, and by that time, there's a lot going on in that wall cavity. We are catching things before they become bad."

    Cable technology

    The idea behind the Detec system is not new. It borrows technology used by the North American telecommunications industry since the early 1980s to protect fiber cable routes from water damage. Its adaptation to the building industry, however, is unique.

    Weinstein's business partner, Roger Hebert, learned about Detec at a trade show and pitched the concept to Weinstein. The partners started talking with Detec leaders and the group decided to make the Reverie a demonstration project for the technology.

    Weinstein said if he's impressed with the performance of the system, he and Hebert will use it in subsequent Marcato phases, which are expected to add up to 400 residential units as well as retail and office space over the next seven years.

    Weinstein is planning to use Detec for the Zocalo housing project, the first phase of the Estancia urban center expected to break ground along the Bothell-Everett Highway in Lynnwood next spring.

    The first Detec system in the United States was recently installed at a student housing complex at the University of Tennessee in Knoxville, and it was quickly put to the test. A fast-paced construction schedule had resulted in a few missing flashings and several unsealed dryer vent penetrations in the walls. Shortly after students moved in, a heavy rainstorm triggered the system.

    The owner was able to work with the building contractor to seal the intrusion points, Townsend said, avoiding future leaks and potential mold growth.

    Peace of mind, for a price

    Detec personnel train and certify the building's electrical subcontractor to install the detection system. Installation costs run between 75 cents and $1 per square foot of living space, said Townsend, meaning the owner of a 1,000-square-foot condo would pay about $1,000.

    Annual monitoring fees would vary, depend on the scope of the system and size of the building. The monitoring of a typical condominium unit would be approximately $120 per year, Townsend said.

    Monitoring costs for structures such as schools or hospitals depend on the number of remote zone sensors in a building, but typically run about $55 per 1,000 square feet per year. A 50,000-square-foot hospital, for example, would cost approximately $2,750 per year to monitor.

    The cost of the system is negligible, Townsend said, when compared to the toll that water damage and associated lawsuits can take on a building owner and its occupants.

    "What if this saves the owner from a major mold litigation suit or construction defect suit?" said Townsend. "That's when the real value becomes apparent."

    The system can be used in any building type, including wood-frame, light-gauge steel, heavy-steel and concrete structures. Installation is possible in new construction as well as renovations or restorations, as long as there is total removal of either the exterior façade or interior drywall to expose sheathings.

    While the Detec system appears to be a solution to the commercial building industry's water intrusion problems, the extent of its usefulness is still questioned by some industry professionals.

    Scott Olson, president of Remco Deacon of Bellevue, a general contractor that specializes in the repair of moisture-damaged structures, wonders if owners will actually take the steps needed to fix water intrusion problems once the Detec system sniffs them out.

    "In my opinion, the more difficult moment as an owner is deciding whether or not to do anything about (water intrusion)," said Olson. "Most of our clients in the multi-family market don't appear to have the dispensable income or reserves to spend money chasing problems with their buildings. It is difficult to get them to take these issues seriously when they can actually see the mold, rot and associated damage, let alone when an alarm tells them there is moisture.

    "Each individual determines what the critical level is, or when they need to take action about water intrusion. Some have a lot more tolerance than others, thus the alarm may not mean much to them."

    Olson said a building, especially a condominium, in which the Detec system was installed would have a higher resale value. Condos are typically difficult to sell because of frequent construction defect and water intrusion problems. Proof of a building's clean track record from a water damage standpoint would likely be a strong selling point, Olson said.

    Insurance assurance

    Detec leaders are working to get the detection system recognized by insurance companies as a way to avoid costly remediation repairs.

    "If this lowers the risk to an insurance company by monitoring the building," said Townsend, "the owner should get a discount on his rate."

    Townsend also hopes that his company will soon be recognized as a point contributor for developers using the U.S. Green Building Council's LEED program, since Detec helps reduce building materials disposed of in landfills and can prevent indoor air quality problems.

    Sheila Bacon is a freelance writer covering the Pacific Northwest's architecture, engineering and construction communities. She can be reached at

    Other Stories:

    Copyright ©2009 Seattle Daily Journal and DJC.COM.
    Comments? Questions? Contact us.