Cleaning Metal Ducts Lined with Fiberglass Insulation

Metal ducts in most cases have fiberglass insulation on them. In HVACs fiberglass insulation is often found in the air handlers, plenums and duct work. Metals ducts are mainly found with two kinds of fiberglass insulated layers. It could be in form of duct liner and duct wrap. The duct liner is a thin coating of fiberglass on the metal surface. The duct wrap is like a blanket-type thermal insulation made of fiberglass. However, cleaning metal ducts lined with fiberglass insulated layer requires a separate set of procedures.

Fiberglass lining on metal ducts often get damaged by:

• Erosion due to the air issuing from the fan in the air handler
• Contamination due to smoke in case of a fire
• Active mold or microbial growth

 You have to schedule a call with a duct cleaning service that have specialized training about handing fiberglass insulated ducts. These service professionals will check if the insulation is in good shape. If it is in good shape and canst and the harshness of cleaning then they will take up the necessary measures and procedures to clean it up. Thereafter they will apply a coating. Coating is done to resist fire and molds. It is a low odor, quick setting, and water-based surfacing material. It has a low viscosity and can be applied with any spay equipment. Coating helps in locking in the dirt, microbial spores, smoke contaminates on the surface of the fiberglass. The coating layer will not allow them to become loose and find their way into your living space. It also renders a more lasting air stream surface that will resist erosion and moisture. The layer is easy to clean.

 If the insulation is not in a good shape then they will recommend replacing it with a new insulation. You also have the option of removing the duct work and replacing it with a new one.

The most common practices for cleaning metallic ducts lined with fiberglass insulation are:

• First the duct s surface is cleaned with contact vacuum. The vacuum has a HEPA filter. The surface is touched with brushes of soft bristle to remove the dust and debris. 

• Once this is over, compressed air is injected through a nozzle. This is done to loosen the debris which is later vacuumed out.

• Power brushing is used to draw the debris at the other end for vacuum extraction. This is a harsh process which often leads to release of fiberglass particles in the airstream.

 Always ensure that the workers who come to your house to clean the ducts follow the procedures which are important to ensure their safety as well as yours.

• The workers should be clad in work uniforms which will include protective clothing, mask respirator, safety glasses.

• If your fiberglass insulation is infested with molds then they should wear appropriate respirators.

• Barrier gloves should be used to prevent fiberglass penetration. Gloves made of nit ride minimize risk of contamination.

• The fiberglass lining should be cleaned in a well ventilated area to minimize exposure due to inhalation.

• You should have a location of eye wash and safety shower for the workers to use them after the work is completed.

• They should use correct cutting tools, cleaning tools, and wet methods to minimize chances of exposure.

• The equipment for cleaning should be placed outside in downwind position. They should be kept at a safe distance from the locations of air intakes and points of entry into the building.

• The carpets and furnishings of the house should be taken care of while cleaning.

• The access holes should be well sealed after the work is over and the components of HVAC should be restored to their original setting.