NW Builder magazine
February 2002, Page 41


BAD SPECS BRING NEW MOLD

In restoration, the original plans aren't necessarily the best.

By Ron Hungarter

Home Construction PlansSometimes even reputable contractors use ill-advised construction practices, leading to serious health problems for homeowners or even lawsuits. Fortunately, this article has a happy ending, but not without effort and compromise on everyone's part.

In one particular instance, fire had seriously damaged a home, requiring that the entire roof structure - including the trusses, sheathing and shingles - be replaced. the owners hired a contractor who specializes in fire reconstruction and gave him specifications from their insurance company.

Unfortunately, both the insurance adjuster and the owner told the contractor to restore the home exactly as it had been, a bad decision. The original specs were flawed, causing this otherwise reputable contractor to install items now known to create serious environmental problems - problems compounded by the contractor's own unwitting recommendation to install two additional gable end vents.

FAULTY VENT SYSTEM CREATES PROBLEMS

As we now know, mixing outlet vent types is a no-no. The more efficient outlet vent transforms the weaker outlet vent into an inlet vent. air then simply short circuits between these two vents, eliminating the needed draw of air flow in from the soffit and then up along the roof sheathing.

The homeowner sold the property shortly after the restoration was complete. During the first winter, the new homeowners noticed the new plywood roof sheathing was dripping wet and beginning to buckle. Worse, a serious black mold had developed in the attic, to which one of the new homeowners was seriously allergic. He broke out in hives and skin rashes, making him both uncomfortable and ill. The problem became so severe that he called a lawyer to discuss a lawsuit against this otherwise reputable contractor. The stage was set for a lose-lose battle.

The attorney hired an inspector, who spotted the cause of the problem and suggested that the homeowners and contractor solve the dispute out of court. The two sides discussed the findings and agreed on a quick and inexpensive resolution to the potentially very serious problems:

  • The contractor agreed to remove the insulation installed over and blocking the intermittent soffit inlet vents to the attic, thus allowing needed inlet fresh air flow into the attic space.
  • The homeowner agreed to pay the contractor for installing additional soffit inlet vents where none currently existed and to install additional soffit inlet vents where intermittent vents were present to provide inlet airflow. The insurance adjuster originally denied this step.
  • The contractor agreed to block off the two large, newly installed gable end vents with plywood, which he had earlier suggested for installation. The power vent transformed the gable end outlet vents into inlet vents, stopping the necessary upward flow of fresh air in from the soffits and along the roof's sheathing. This airflow is needed to eliminate the condensation that helps mold grow.
  • The contractor agreed to install continuous baffled ridge vents along the entire intersecting gable roof line, another solution the adjuster had denied. Baffled ridge vents are the most efficient way to ventilate attics. Wind creates a negative pressure over that vent, much like that of an airplane wing, sucking out the heat and humidity from the attic efficiently and quietly.
  • The homeowner agreed to seal off the power roof vent fan from the inside, using plastic to prevent an upward pull of air by the baffled ridge vents from the soffit vents. This kept the attic air cool, dry and mold-free.
  • The contractor agreed to kill the existing mold with a bleach solution, then seal the affected surfaces with paint.
  • The allergic homeowner is no longer subjected to mold in his newly purchased home, the plywood roof sheathing is no longer wet and swollen, the air is flowing naturally in and out of the attic, the contractor is relieved to know that a problem has been eliminated, and no one is spending excessive amounts of money and time on litigation. NWB

    Ron Hungarter is a licensed contractor, real estate inspector and roofing tools inventor. He can be reached at www.ronhungarter.com.

    e-mail Ron Hungarter

    2001 - 2011 Ron Hungarter Associates, Inc.