For many years, fibrous glass or fiberglass, has been the standard material for thermal and acoustic insulation in air conditioning systems. As the health hazards of asbestos became more broadly known and the use of it was phased out from the late 60’s to early 80’s, fiberglass became the “default” insulation to be used in almost every phase of construction including air conditioning.
While the U.S. Department of Health and Human Services issued a report in 1994 stating that fiberglass is “reasonably anticipated to be a carcinogen,” they issued a disclaimer that this did not apply to general consumer exposure. The disclaimer did not go on to explain whether a “general consumer” is a different species of human or not, but the inference is that a general consumer has different exposure levels than one working in the industry.
OSHA standards states the following:
It is, however, interesting to note that currently, the largest manufacturers of fiberglass building and insulation materials are the very same companies who were previously the largest manufacturers of asbestos products and who for decades asserted that asbestos posed no health hazards. They have each since filed bankruptcy and restructured to form a special “personal injury trust” to handle the hundreds of thousands of lawsuits resulting in billions of dollars of settlements and judgments.
As noted above, whether fiberglass is “safe” or not is still a question that hasn’t been fully answered. However, there are things we DO know. The only generally agreed upon fact is that fiberglass is an irritant, something that anyone who has worked with or around that pink fiberglass insulation in their attics has personally experienced. Contact with fiberglass can cause skin irritation, as well as irritation to the eyes and upper respiratory system.
The point of this article, however, is not to debate the health implications of fiberglass insulation.
The point is that there is obvious concern amongst consumers, contractors and health professionals as well as air conditioning manufacturers regarding the use of fiberglass. And from our observation, these same people are looking to use other materials than fiberglass to provide insulation.
Since 1995, Machado has been re-insulating fiberglass lined ductwork and air handling units with non-fiberglass insulation, most commonly Astrofoil or Reflectix, reflective bubble wrap insulation products which contain no fibrous insulation.
For many years, Astrofoil and Reflectix have been the go-to proven viable alternative for internal fiberglass insulation. It is clean, lightweight, and hey, it looks great!
Astrofoil and Reflectix, the good:
This astrofoil had been installed 11 years prior to this photograph and looks practically new. Any foil reflective insulation will hold up well if properly installed.
There are few downsides to using reflective non-fiberglass liner, but here they are - the not so good:
In addition to Astrofoil and Reflectix, there are other alternative insulating materials, some of which we have done some tests on and others we have yet to check out.
These would include Bonded Logic Natural Fiber Duct Liner, which is actually made out of old blue jeans, treated and remanufactured into HVAC duct liner and is becoming quite the rage in sustainable and environmental circles. Stay tuned - we have gotten some samples and are going to be testing it out. If the surface proves to be as rugged as it appears, then this may be able to be installed without the astrofoil on top of it thereby saving money and time.
To conclude, there are alternatives to fiberglass insulation for air conditioning systems.
Armaflex is a closed-cell elastomeric foam material designed specifically for use as a duct liner. We have little experience with Armaflex so cannot judge its longevity or UV resistance. It is a product which is non-toxic and resistant to microbial growth. It is more expensive than fiberglass or Reflectix.
K-flex Duct liner is another closed cell duct liner with similar properties to Armaflex.
There are numerous other products, from man-made fibrous material that is not fiberglass, styrofoam-type insulation, cotton based, treated paper. Some have been short lived, some are difficult to come by or very difficult to work with.
We continue to look into alternatives that are more healthful, more easily accessible, less expensive and as we lead the way, we’ll let you know!