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Improvements   >   Duct Leakage
Quick Fact

In many older homes, the duct system is in such poor condition that only removal and replacement will solve the problem.

28-year old ductwork under typical attic stress conditions.  Removal and replacement is the only viable option.

New efficient metalized R-6 ductwork substantially increases efficiency and deliverability.

Quick Fact

According to the Department of Energy, an average duct system is responsible for 25% - 40% energy loss.

When it comes to duct testing and sealing, professionals test....the rest guess.

Duct Leakage

    Before After    

Air distribution ducts are a series of connecting pipes that deliver warm or cool air to your living space and maintain a comfortable temperature within your home. Typically, ductwork is hidden away in attics and in crawl spaces under homes, so costly leaks go undetected, leading to one of the major causes of high utility bills. According to the Department of Energy, an average duct system loses 25% to 40% of the heating and cooling energy put out by the central furnace or air conditioner. This hidden problem can cost a homeowner several hundred dollars per year in avoidable utility bills.

Often ignored when considering energy efficient upgrades, undetected duct leakage can affect your family’s health, comfort, and budget. Imagine purchasing an economy car that is rated for 40 miles per gallon, but due to a gas line leak, is only getting 15 miles per gallon. How fast would you address the problem and have it fixed? Just like the example of the car, leaky ductwork will not only increase your utility bills, but force your heating and air conditioning system to run longer and work harder to maintain comfort levels. Over a period of years, all duct systems separate and fall apart; therefore, making duct repairs one of the most cost-effective energy improvements you can invest in.

Breathe Better Air
How Duct Leakage Can Affect Your Family's Health 

Leaks in the duct distribution system can pull pollutants and irritants directly into your house. These pollutants are drawn into the duct system from the attic, crawl space, or garage and are then redistributed throughout your house when your furnace or air conditioning system is operating.

Common pollutants and irritants that are drawn into your house by duct leakage include:

  • Pollen and dust
  • Insulation material fibers
  • Truck or automobile exhaust
  • Mold and mildew spores
  • Vapors from stored chemicals and insecticides
  • Carbon monoxide

Because we spend a large percentage of time indoors, the quality of air in our homes is critical. In many houses, excessive duct leakage is the main cause of poor indoor air quality and affects the health of the entire family.

Duct Leakage
The Solution
Due to the development of specialized diagnostic tools, it is now possible to test a duct system and measure the extent of the problem. Trained technicians use a duct blaster to pressure test your duct system for air leaks, much the same way a plumber pressure tests your water pipes for leaks. After sealing the registers and grills, the duct blaster fan is connected to the duct system to force air through all the cracks and gaps in the ductwork. An accurate leakage measurement is then made using the airflow and pressure monitor connected to the diagnostic system.

Sealing Your Duct System
After pressure testing your duct system, the system can be sealed and repaired. It is important that only qualified contractors with trained technicians perform duct repair or replacement in your home. Professionals utilize recognized and approved duct repair techniques and UL listed materials to properly seal your duct system.

Today’s technology and training allows contractors to professionally test, seal, and retest to assure homeowners that the problems are solved and the results are documented.


Tight ductwork is a critical component of the "Whole House as a System" approach.

25-year-old duct after
being opened

Diagnostic duct testing

Supply plenum sealed with UL-listed duct sealant

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