Commercial HVAC Maintenance • Lined Ducts

Cleaning Internal Fiberglass Ductwork

Commercial air duct cleaning for lined systems requires specialized care. Unlike bare metal, fiberglass insulation is fragile and easily damaged by standard methods. Ductworks Inc. uses liner-safe tools and industrial vacuums designed to clean these sensitive systems effectively.

Project Planning • Access and Openings

Good access is the key to a successful clean

Planned openings protect the liner and the duct

You cannot clean or check what you cannot reach. Ductworks Inc. solves this by combining smart access points with tools made to move safely through lined systems. Our technicians are experts at creating service openings to ensure we reach every inch. Just as importantly, we plan how to close the system before we ever cut into it.

Limit access points

Fewer holes mean less disruption and less resealing work. Careful planning ensures we clean the whole system without cutting too much.

Place openings with intent

Doors work best near main trunks and turns. This makes checking our work easier because tools and cameras can see the full path.

Support tool reach

Correct sizing lets air tools travel the full length of the duct freely. This prevents “forcing” the gear, ensuring we clean effectively while protecting the soft liner.

Pre-Planned Sealing

We cut every opening with the final seal in mind. We preserve a clean, flat surface to guarantee a permanent, airtight closure once the job is done.

Cleaning Methods • Liner-Safe Removal

Thorough Cleaning Through Controlled Techniques

Using Proven Techniques for Lined Air Ducts

In soft ducts, “more power” does not mean a better clean. We follow a strict process of controlled movement and steady airflow. Too much force from stiff brushes can shred the surface, while too much vacuum pressure can peel the liner apart. We choose our method based on one goal: the best result for your specific system. Whether we use contact vacuuming or air tools, we prioritize a thorough clean that keeps the insulation safe.

Negative Pressure Air Washing

Using compressed air tools, we systematically push dirt off the duct surfaces. This moves debris toward the vacuum while negative pressure ensures no dust escapes into the room.

Manual Soft-Bristle Cleaning

We use soft brushes to gently loosen debris by hand. This hands-on method lifts stuck dust without harsh machines, preserving the condition of the insulation.

HEPA-Filtered Containment

Our vacuums use hospital-grade HEPA filters. They capture 99.97% of particles down to 0.3 microns. This keeps the workspace safe and ensures fibers and dust are never blown back indoors.

Gentle Mechanical Cleaning

We use specialized tools to clean interior surfaces safely. This gentle approach lifts dust off the surface without damaging the internal insulation or liner.

Methods to avoid on internal liner

Avoid moisture or steam. Water can stay trapped and damage insulation.
Avoid aggressive scrubbing. Stiff tools can shred the surface and expose fibers.
Avoid “one-size-fits-all” methods. Match the method to the liner’s condition.

Finish Work • Closure and Sealing

Closure Restores Airtight Performance

A Clean System Requires a Tight Seal

Airtight, Permanent Closures— A thorough clean is wasted if the system isn’t sealed correctly. At Ductworks Inc., our process makes your ducts airtight again. We follow NADCA standards by installing panels with a strong overlap, ensuring a tight seal.

Proper closure protects the system and lowers the chance of leaks later. Clean work also makes it easy to check the results during the final inspection.

Guide to Internally Insulated Ductwork • 4 Part Series

Commercial Air Duct Cleaning Resources

What Is Fiberglass Duct Liner? A Colorado Facility Manager’s Guide to Internally Insulated Ductwork

Next Steps • Commercial Support

Commercial Estimate Request

If your facility includes internally lined ductwork, we can build a practical cleaning and inspection plan. Before scheduling work, we review access, liner condition, and verification needs.

Request a Commercial Estimate

Cleaning Internally Lined Ductwork: Protocols for Commercial Facilities