Although good building techniques should help prevent mold, as many contractors know, it doesn't always work that way.

What happens after mold has found its way inside a building was the subject of a seminar during the American Society of Heating, Refrigerating and Air-Conditioning Engineers Winter Meeting, Jan. 25-29 in Chicago. A panel of engineers talked about remediation projects they had been involved in and explained what it took to get rid of the mold inside.

Holley Bailey, an engineer with Bailey Engineering Corp. in Palm Beach Garden, Fla., showed how a building's "envelope" - the structures that enclose a building - affect mold growth on the inside.

Bailey said mold has become "something that is on everybody's hot plate."

Mold problems are made worse, she said, by construction problems such as gaps, layering things in the wrong order and design flaws. With the increasing tightness in construction schedules, jobs that should only be done under certain weather conditions are being performed at the wrong time.

Poor explanations

"Try to explain to the construction manager that we can't apply this today because it's only 45 degrees outside¿ (it) doesn't happen in the real world," she said.

Bailey showed several slides of moisture in a home, including mold on a windowsill and rust on a light-switch cover. "Sometimes we have some things occur in some interesting places."

Such problems are preventable, engineer Ron Bailey said during his presentation on mitigating microbial growth in hvac systems.

"Many of these failures could have been avoided by following the (correct) procedures, fundamentals and guidelines," Ron Bailey said.

Too many people in the construction industry do not learn enough about preventing mold, he said, adding that in some cases, they do not follow what they already know. They don't "understand that the tools at hand cause a lot of _these failures."

Ron Bailey showed pictures of a mold outbreak at a Florida courthouse. Workers had long complained of feeling ill in the building before mold was discovered in the building's hvac system, he said.

The inability of the system to keep workers comfortable in the humid climate had contributed to the situation. Court employees were constantly adjusting the thermostats, Ron Bailey said.

"They were just trying to get their people comfortable in there. They were trying it any way they could," he said. But "For every degree that they turned it down below 73, the problems went up exponentially."

In the end, it took more than $28 million to fix a courthouse that only cost $9 million to build. The contractors involved in the building's construction became involved in a $22 million lawsuit, all of which Ron Bailey said could have been avoided.

With the public's growing concerns over mold and indoor air quality, the problems at the Florida courthouse are another example of why engineers are also becoming public-health specialists, he said.

Ron Bailey then showed pictures of mold growing in a hotel room. The wall covering was to blame, he said.

"After this number of years, there is no excuse that someone should not know that you don't apply a vinyl wall cover in a humid climate," he said. "This is a message that the hospitality industry has not gotten."