Duct Leakage Test in King Of Prussia, PA

How a Duct Leakage Test Is Conducted

To conduct a proper duct leakage test in King Of Prussia, PA, your technician first seals all supply and return registers except the main return or air handler. A duct blaster — a specially calibrated fan — is then connected to the opening. It depressurizes the duct system to expose areas where air is leaking.

The duct blaster uses a precision pressure sensor to monitor airflow and pinpoint leaks throughout the ductwork without interrupting your home environment. A duct leakage test — sometimes called a duct blaster test — detects air loss in the duct system, allowing you to apply the most suitable sealing solutions.

duct leakage test is straightforward, clean, and designed to be non-intrusive for residents. Most tests in King Of Prussia, PA are wrapped up in 30 to 60 minutes, with improvements that continue to boost comfort and efficiency for years.

How to Measure Duct Leakage

Duct leakage is tracked in cubic feet per minute (CFM) per 100 square feet of conditioned living area. Your technician uses a nanometer to register small pressure differences, which help calculate how much air is leaking from the ducts. Understanding this number gives you insight into problem areas, helps you plan improvements, and ensures your home meets local energy code requirements in King Of Prussia, PA.

Cost of Excessive Duct Leakage

If you’re experiencing spikes in utility bills, uncomfortable temperature variations, or ongoing HVAC repair needs, duct leakage may be to blame. According to ENERGY STAR, homes with leaky ducts routinely lose 20% to 30% of conditioned air. Hot or cold outside air creeping into your system forces the HVAC to work inefficiently, increasing energy spending and reducing comfort.

Overworked equipment also increases the likelihood of breakdowns and drives up repair costs. Proper duct sealing helps protect and extend the long-term lifespan of your HVAC system, minimizing the need for repeated maintenance.

Duct leaks can also let dust, mold spores, moisture, and other pollutants enter 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 instructs that new homes incorporate fully sealed duct systems using high-efficiency materials, including mastic, foil tape, and insulation. But what about leaks located deep within walls or ceilings?

Aerosol sealing technology (AeroSeal) is an effective solution for reaching hidden ductwork leaks. To perform this method, all vents are sealed off except for one access point. The HVAC system is isolated, and a machine is connected to the duct system. It pressurizes the ducts and sends out a fine aerosol mist that seals tiny openings traditional sealing cannot reach.

This method is effective at treating small to medium leaks. However, big openings may still need to be addressed with manual mastic-and-tape sealing. Technicians conduct duct leakage test before and after aerosol sealing to see how much the leakage dropped and ensure the treatment worked properly.

Common Areas of Duct Leakage

The most common location for air leakage in ducts is the joints. Ductwork includes several metal sections pressed together with tight fittings and metal bands, but those connections are almost never airtight.

As your HVAC system runs through seasonal heating and cooling, the ducts experience ongoing expansion and contraction. Over time, this movement leads to joint loosening, generating gaps and leaks — a clear reason duct leakage test is recommended for new and older homes in King Of Prussia, PA.

Many energy auditors detect duct leakage by physically checking the ducts and using a small tool to assess the width of joint gaps. If your duct system is unsealed with mastic and approved tape, air leakage is almost certainly occurring.

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

To achieve a passing duct leakage result, your system must come in under 4 CFM per 100 square feet with the air handler, or 3 CFM per 100 square feet when the air handler is removed. For new construction, you must pass a duct leakage test before the home can be approved for an occupancy certificate.

If your home in King Of Prussia, PA cannot achieve a passing duct leakage score, you are likely wasting money on heating and cooling — and increasing wear on your HVAC system over time. Meeting the 3–4 CFM requirement is significant not only for meeting local code but also for maintaining optimal comfort and efficiency in your home.

Your technician will also give informed guidance on addressing leakage problems, enabling you to pass the test, reduce energy bills, and enhance your home’s performance.

Local Energy Audits — affordable duct leakage test in King Of Prussia, PA

Local Energy Audits proudly delivers services across King Of Prussia, PA and the surrounding neighborhoods. We specialize in locating duct leakage and energy inefficiencies with our blower door and duct leakage tests. Whether it’s a new build or an existing home, we’re here to help.
If you’d like to schedule a test, call us during business hours or contact us online to request an appointment.