Duct Leakage Test in Upper Darby, PA

How a Duct Leakage Test Is Conducted

To begin performing a duct leakage test in Upper Darby, PA, your technician closes off all supply and return registers except the main return or air handler system. A calibrated duct blaster is then secured to the opening. Its function is to depressurize the duct system, creating conditions that highlight any escaping air.

The duct blaster teams up with a precision pressure sensor to measure airflow accurately and locate duct leaks without affecting your home. A duct leakage test — sometimes referred to as a duct blaster test — uncovers air leaks in your ductwork so you can determine the ideal sealing approach.

duct leakage test is efficient, clean, and performed without bothering residents. Most tests in Upper Darby, PA take only 30 to 60 minutes, yet the comfort and efficiency gains can last for years.

How to Measure Duct Leakage

Duct leakage is defined in cubic feet per minute (CFM) per 100 square feet of conditioned space within the structure. Your technician uses a nanometer to evaluate small pressure shifts that signal air escaping through the ducts. Understanding this number helps you identify problem areas, evaluate potential improvements, and determine whether your home meets local energy code requirements in Upper Darby, PA.

Cost of Excessive Duct Leakage

If your home suffers from costly utility bills, uneven comfort levels, or persistent HVAC repairs, duct leakage may be contributing. According to ENERGY STAR, most households lose 20% to 30% of their heated or cooled air because of duct leaks. If hot or cold air from outdoors enters your system, your HVAC works harder than necessary, causing energy costs to rise and comfort to fall.

Overworked equipment also causes additional breakdowns and increases repair costs. Proper duct sealing helps promote the long-term integrity of your HVAC system, extending its lifespan and limiting continued maintenance needs.

Duct leaks can also pull in dust, mold spores, moisture, and numerous contaminants into the duct system. This can aggravate allergies, lower indoor air quality, and eventually lead to costly structural damage hidden behind walls or ceilings.

How to Properly Seal Ductwork in an Old Home

The 2015 IRC/IECC calls for new homes to include duct systems that are completely sealed using efficient materials such as mastic, foil tape, and insulation. But what about leaks that are hidden far behind walls or ceilings?

Aerosol sealing technology (AeroSeal) offers a method to access hidden leaks deep within ductwork. To start this method, all vents are blocked except for one access location. The HVAC system is isolated, and a machine is attached to the ducts. It pressurizes the ducts and distributes an ultra-fine aerosol sealant to fill small gaps and holes that manual sealing methods can’t access.

This method is very effective for minor to moderate leaks. However, substantial openings may still need traditional sealing with mastic and tape. Technicians carry out a duct leakage test before and after aerosol sealing to assess how much leakage has improved and ensure the treatment was effective.

Common Areas of Duct Leakage

The most common point where ducts leak air is along the joints. Ductwork is made from multiple metal pieces pressed together with tight fittings and metal bands, but these connections are rarely completely airtight.

As your HVAC system transitions between warm and cool air throughout the year, the ducts expand and contract. Over time, this movement shifts and loosens the joints, resulting in gaps and leaks — which is why all homes in Upper Darby, PA, new or older, benefit from duct leakage test.

Many energy auditors identify duct leakage by moving their hands along the ducts and using a small tool to check the width of joint openings. If your duct system lacks proper sealing with mastic and approved tape, there is a high chance that leakage is taking place.

What Is an Acceptable Amount of Duct Leakage per Energy Code?

To achieve a passing duct leakage result, your system should fall under 4 CFM per 100 square feet with the air handler, or 3 CFM per 100 square feet when the air handler is absent. For new construction, passing a duct leakage test is required before a home can receive an occupancy certificate.

If your home in Upper Darby, PA does not pass its duct leakage inspection, you’re likely paying higher heating and cooling bills — and stressing your HVAC system over time. Meeting the 3–4 CFM requirement is critical not just for code compliance, but also for defending your home’s comfort and energy performance.

Your technician will also offer expert guidance on fixing leakage problems so you can earn a passing score, reduce utility costs, and enhance your home’s overall performance.

Local Energy Audits — affordable duct leakage test in Upper Darby, PA

Local Energy Audits proudly serves customers throughout Upper Darby, PA and surrounding areas. We specialize in finding duct leakage and energy inefficiencies through blower door tests and duct leakage tests. Whether you’re constructing a new home or upgrading an older one, we’re ready to assist.
If you’d like to book a test, call us during business hours or contact us online to request an appointment.