Fiber glass takes a bash, along with contractors
Contractors were certainly bashed at ASHRAE forum “IEQ and Fiber Glass: What’s Your Experience,” part of the recent ASHRAE 2000 Winter Meeting here. Many in the audience blamed contractors for faulty installation, thus giving fiber glass duct lining a bad rap.
“We have to police [the contractor] when it [fiber glass duct lining] is installed,” complained one attendee, who later identified himself as a design engineer. “You really have to watch what is done with it.”
Vested interestForum moderator Lawrence Gelin of Johns Manville naturally had an interest in the topic, as he is employed by a manufacturer that makes fiber glass duct liners and duct board.
To say the least, the use of fibrous duct liners remains a contentious issue for many building owners, engineers, and architects. Control of noise from equipment is often sacrificed in order to prevent or reduce the perceived risks from using fibrous acoustical materials.
Gelin opened the forum noting that Steve Taylor, P.E., wrote an informative article concerning fiber glass (“Duct Liner: An Engineer’s Perspective”) in the inaugural issue of IAQ Applications, ASHRAE’s new quarterly publication.
Gelin then wanted to know the perception of fiber glass in the engineering community. When the subject of fiber glass was brought up during a project discussion, Gelin wanted to know who generally brought up the subject and what was that person’s major concern.
One engineer noted that it was not allowed in a hospital setting, noting that “Inspection control people do not allow fiber glass lining downstream of a fan.” A manufacturer’s rep noted that in most of his cases, it was the homeowner who questioned fiber glass.
“They are afraid of loose fibers getting into the house,” he said. “It’s that asbestos-like scare.”
Still another engineer brought up the “quality control issue of the installation,” plus the questionable life of the product.
“The major concern with the product is that this is an expensive addition in a retrofit situation,” he said.
Time to increase quality control?Gelin wanted to know what information was used to make a decision regarding fiber glass. One noted that he passed along NAIMA pamphlets, to let the questioning party read up on the subject before making a final decision.
Gelin also wanted to know if there was a lack of information regarding the topic, but he did not get a definitive answer from the 20 or so attendees in the conference room.
When it came time to produce a solution to the fiber glass question, Gelin wanted to know what the audience did. Among the answers from the field included “a creative solution,” “live with the noise,” “spend more money,” and “get a new product.” And, of course, there was the contractor’s involvement.
“We have to increase quality control,” said one engineer. “We have to reinforce the knowledge of maintenance people and contractors.”
When asked what was unknown in the field regarding fiber glass and if there were still concerns, many pointed to the contractor and facility-maintenance engineer.
“The control over the life of the building is out of our control,” said one engineer. “When we specify it, we can make sure it is put in correctly, but once we’re gone, we’re gone. That’s it.”
If you have water ...How can the issue be addressed? What information is lacking? The answers to both questions varied.
One asked that building owners be surveyed, to make sure they understood the product and what it can accomplish. Even if it was installed properly, if a mechanical system is not properly maintained, there’s the chance of condensation accumulating in the ductwork, ruining the lining.
“The biggest fault is in the maintenance,” said one attendee. “Not having a good filtration system [is bad] and keeping the system dry is very important and needed.”
When asked if ASHRAE should have a role in creating standards for fiber glass and its installation, many responded that that’s what the commissioning process was for.
“However, when you have water [in the system], you are going to have problems,” said one.
Plain and simple, said another, “The installation has to be good. Service has to be good, too.”