How Much Cooling Am I Losing Through Leaky Ducts?

The number you'll find everywhere is 20 to 30 percent. It comes from ENERGY STAR, it's accurate, and it describes a typical house. It does not describe your house.

That distinction matters more than it sounds. A typical range averages tight systems against badly leaking ones. Your ducts could be well above that range or comfortably below it, and reading an article won't tell you which.

What will tell you is a duct leakage test, which measures what's actually escaping rather than estimating it. Below, you'll see where that 20 to 30 percent figure comes from, why your number is probably different, and the specific signs that put a house on the worse end of the range. You'll also learn the four places leaks usually hide. Berkeys has worked in Southlake since 1975.

In a typical house, about 20 to 30 percent of the air moving through the duct system is lost to leaks, holes, and poorly connected ducts, according to ENERGY STAR.

• That's a range, not your number. Your system could be tighter, or considerably leakier.
• The only way to know yours is a duct leakage test, which measures what's actually escaping.
• Signs it's worse than average: ducts running through an attic or garage, rooms that won't hold temperature, and kinked flexible duct.

Where the loss goes matters too. Air escaping into a hot attic isn't just wasted. It's cooling you paid for, delivered to the wrong place. Want your actual number? Learn about our HVAC contractor in Southlake.

The figure comes from ENERGY STAR, and it's worth reading in full rather than as a headline number.

In houses with forced-air heating and cooling, ducts carry conditioned air through the building. ENERGY STAR reports that in a typical house, about 20 to 30 percent of the air moving through that duct system is lost due to leaks, holes, and poorly connected ducts.

The consequence they describe is the part worth noticing. Higher utility bills, and difficulty keeping the house comfortable no matter how the thermostat is set.

That last phrase explains a frustration people rarely connect to ductwork. If the system is producing cold air and a third of it never arrives, adjusting the thermostat doesn't solve anything. You're not fighting the setting. You're fighting delivery.

So the number is real and well established. What it isn't is a measurement of your home, which is the next section.

A typical range is an average, and averages hide the thing you actually want to know.

Somewhere in that 20 to 30 percent are homes losing far less, with sealed ducts running through conditioned space. Also in it are homes losing considerably more, with disconnected runs dumping cold air into an attic all summer.

What pushes a house toward the worse end:

• Ducts running through an attic, crawlspace, or garage
• Older systems where connections have loosened over time
• Flexible duct that's kinked, crushed, or poorly supported
• Previous work that disturbed connections and didn't seal them properly
• Runs that were long or awkward from the start

What pulls a house toward the better end:

• Ducts inside conditioned space
• A newer, well-executed installation
• Sealing work that's already been done properly

The honest answer to "how much am I losing" is that nobody knows until someone measures. Everything before that is a reasonable guess wearing a confident number.

A duct leakage test does what the name suggests. It measures how much air escapes the duct system rather than estimating it from the age of the house.

The principle is straightforward. The system gets pressurized, and the equipment measures how much air has to be pushed in to hold that pressure. Air that escapes has to be replaced, so the amount needed tells you the amount leaking.

What you get back is a number for your house. Not a range from a national study. Your ducts, measured.

A test often points toward locations as well. Where the leaks concentrate matters for deciding what to do about them, since a disconnected run in an attic is a different repair than a dozen small gaps at register boots.

That's the difference worth paying for. A statistic tells you leaky ducts are common. A test tells you what yours are doing.

Before any test, there are indicators you can check yourself. ENERGY STAR names these among the signs of poorly performing ducts.

Your ducts run through an attic, crawlspace, or garage. This is the first one on their list, and it describes a great many homes in this area. Air escaping into those spaces is gone entirely.

You have tangled or kinked flexible ducts. Flex duct kinks when it's crowded, unsupported, or routed around obstacles. A kink restricts airflow even when nothing is leaking.

Rooms are uncomfortable no matter where you set the thermostat. This is the symptom people live with longest, because it reads as a quirk of the house rather than a fault.

Your bills are higher than they should be. Harder to judge on its own, but meaningful alongside the others.

The house is dusty. Leaks pull in air from wherever the ducts run, and attics are not clean places.

Any one of these is worth a closer look. Several together make a test worth scheduling.

ENERGY STAR identifies four common duct problems. They're worth knowing because they're where a technician looks first.

Leaky, torn, and disconnected ducts. The obvious category, and the most consequential. A fully disconnected run delivers everything it carries to an attic.

Poorly sealed registers and grills. The connection between duct and register boot is a common gap, and it sits right at the point where the air was supposed to arrive.

Leaks at the furnace and filter slot. This one surprises people, because it's inside the house at the equipment itself. Gaps around the filter slot and cabinet connections let air escape before it ever reaches a duct.

Kinks in flexible ductwork. Not a leak, but it belongs on the list. A kinked run restricts airflow the same way a bent hose does, and the room at the end of it never gets what it should.

Notice that two of the four aren't in the attic at all.

Tired of guessing from a national average? Our Southlake team can measure your duct system and tell you the actual number. You'll get transparent pricing before any work begins. Call (817) 481-5869 for HVAC service in Southlake.

We answer calls 24/7. Want to see what your Southlake neighbors say first? Read our Southlake Google reviews.

Business Address: 1070 S Kimball Ave Suite 131, Southlake, TX 76092