Duct Leakage Test in Berwyn, PA

How a Duct Leakage Test Is Conducted

To begin performing a duct leakage test in Berwyn, PA, your technician closes off all supply and return registers except the main return or air handler system. A duct blaster — a precision-calibrated fan — is then fitted to the duct opening. By depressurizing the system, it makes all air leaks much easier to detect.

The duct blaster collaborates with a precision pressure sensor to evaluate airflow and locate leaks throughout the ductwork without disturbing your household. A duct leakage test — often known as a duct blaster test — exposes duct air loss, allowing you to apply the most effective sealing techniques.

duct leakage test is straightforward, clean, and designed to be non-intrusive for residents. Most tests in Berwyn, PA take around 30 to 60 minutes, but the efficiency and comfort improvements can last for many years.

How to Measure Duct Leakage

Duct leakage is evaluated in cubic feet per minute (CFM) per 100 square feet of conditioned space inside the home. Your technician uses a nanometer to measure tiny pressure differences, making it possible to determine how much air the ducts are losing. Understanding this number helps you reveal problem areas, consider enhancement strategies, and validate that your home meets local energy code requirements in Berwyn, PA.

Cost of Excessive Duct Leakage

If you’re seeing higher energy bills, irregular heating or cooling, or frequent HVAC malfunctions, duct leakage may be at fault. According to ENERGY STAR, leaking ducts cause the average home to lose 20%–30% of conditioned air. Air entering from outside—whether warm or cold—makes your HVAC operate harder, causing energy costs to climb and comfort to decrease.

Overworked equipment also accelerates wear and tear, resulting in more breakdowns and costly repairs. 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 bring dust, mold spores, excess moisture, and other impurities into the duct system. This can intensify allergy symptoms, harm indoor air quality, and cause long-term structural damage behind walls or ceilings.

How to Properly Seal Ductwork in an Old Home

The 2015 IRC/IECC requires new homes to have fully sealed duct systems using modern, energy-efficient materials such as mastic, foil tape, and insulation. But what happens when leaks are hidden deep inside walls or ceilings?

Aerosol sealing technology (AeroSeal) enables effective sealing of leaks hidden inside ducts. To complete this method, all vents are closed off except for one access opening. The HVAC system is isolated, and a machine is linked to the duct system. It pressurizes the ducts and releases a fine aerosolized sealant that fills small gaps and holes that traditional sealing methods cannot reach.

This method works efficiently for small to medium leaks. However, larger gaps usually require manual sealing using mastic and tape. Technicians complete before-and-after duct leakage tests to measure leakage reduction and ensure the aerosol sealing was effective.

Common Areas of Duct Leakage

The most frequent point of air leakage in ductwork is the joints. Multiple metal parts are pressed together using tight fittings and metal bands, although these junctions are seldom airtight.

As your HVAC system operates in varying temperatures across the year, the ducts undergo expansion and contraction. Over time, this movement causes the joints to loosen, creating gaps and leaks — which is why a duct leakage test is recommended for both new and older homes in Berwyn, PA.

Many energy auditors verify duct leakage by feeling around the ducts and using a small tool to assess the opening size at the joints. If your duct system is missing mastic and approved tape sealing, there’s a significant chance that air leakage is happening.

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

To achieve a passing duct leakage result, your system needs to be under 4 CFM per 100 square feet when the air handler is installed, or 3 CFM per 100 square feet when it isn’t. For new construction, a passing duct leakage test is a required step before final occupancy certification can be awarded.

If your home in Berwyn, PA doesn’t pass a duct leakage test, chances are you’re paying more for heating and cooling — and adding long-term stress to your HVAC equipment. Meeting the 3–4 CFM requirement matters not only for code compliance, but also for protecting your home’s comfort and reducing energy waste.

Your technician will also provide expert strategies to address leakage concerns, helping you achieve a passing score, bring down utility bills, and boost home efficiency.

Local Energy Audits — affordable duct leakage test in Berwyn, PA

Local Energy Audits proudly serves homeowners, contractors, and builders throughout Berwyn, PA and nearby regions. We specialize in revealing duct leakage and energy inefficiencies through blower door and duct leakage test. Whether your project is new or existing, we’re here to assist.
If you’d like to schedule a test, call us during business hours or contact us online to request an appointment.