11/11/2025
IMPORTANT INFORMATION FOR PEOPLE WHO HAVE HOMES THAT HAVE FIBERGLASS DUCTBOARD DUCT:
Sometimes we are called to a house to clean the ducts, and we discover that the ducts are constructed of a material known as ductboard. Most homeowners have no idea of the adverse effect that these systems can have on the long-term health of the occupants, These systems also present a particular challenge to the duct cleaning technician, since the ductboard is much less durable than systems that are constructed of galvanized sheet metal and if the proper cleaning procedure is not selected and followed, duct surfaces can be damaged.
Once fiberglass ductboard is identified, it is our policy to inform our customers of this and to explain the cleaning methods and options available so that he or she is well-informed in order that he or she may make an intelligent decision as to how to move forward.
Ductboard is a dense rigid board made from fiberglass strands bonded with resin. The interior surface of the ductboard, which is in the airstream, can break down over time and/or be compromised if aggressive methods of duct cleaning are employed, such as those which are regularly used when cleaning sheet metal ducts. For this reason, we recommend cleaning the ducts using non-agitation methods. A good analogy would be bringing your car to a touchless car wash which sprays your car with water, rather than scrubbing the surfaces of your car with brushes and clothes.
Since ductboard ducts are more susceptible to becoming damaged, if agitated, we opt to use the safest method of cleaning when cleaning them (air washing) whereby no agitation takes place. The unfortunate truth is that cleaning ducts, using this method, will result in a higher percentage of material that will not be removed from the ducts.
If your goal is to have a net result similar to that which is possible for galvanized sheet metal duct distribution systems, consider investing in having the interior surfaces encapsulated, following a good thorough duct cleaning, using the conventional method.
When ducts are encapsulated, a sealer is sprayed onto the interior surfaces of the duct which forms a durable, flexible film that resists degradation while locking down loose particulate. The process of encapsulating ducts does not come cheap. Expect to pay upwards of $3,000 per system to have it done.
A third option, and in my opinion the best one, is to replace the ductboard with a galvanized sheet metal duct distribution system. All duct joints will need to be sealed, to satisfy the building code, and most ducts will, also, need to be insulated. I recommend insulating the ducts using a non-fiberglass product, such as Reflectix. The option to replace the ducts, seal the joints and insulate them is also the most expensive one, costing many more thousands of dollars than the encapsulation option.
It is important to be mindful that ducts need to be cleaned every 4 to 7 years, and in some cases (For sensitive groups), every year or two, so having a good durable galvanized sheet metal duct distribution system will go a long way towards alleviating concerns surrounding the possibility of ducts being damaged during future cleanings.
If you have not yet done so, I recommend that you also read the attached article which sheds some light on this subject, as well.
If you suspect that you have fiberglass ductboard ducts in your home and if you have any questions, please call 413-782-8682 and we will be happy to help you in any way that we can, including recommending an HVAC contractor who can encapsulate or replace your duct distribution system.
