In many homes the ducts run through an attic or crawlspace. Every joint and seam is a place air can escape, and air lost there is air you paid to heat or cool. In older homes, it's common for a meaningful share of a system's air to never reach the rooms.
Signs your ducts may be leaking
- Rooms that never get comfortable, especially the ones farthest from the equipment. See one room too hot or cold.
- Weak airflow from some vents while the system runs normally.
- High energy bills without a change in how you use the system.
- A dusty house, or dust streaks around vents, because leaky return ducts can pull in dusty attic or crawlspace air.
- Ducts you can see that are crushed, kinked, disconnected, or patched with cloth tape that's peeling.
- An attic that's very hot in winter or cool in summer near the ducts.
How it's found
A duct leakage test pressurizes the duct system with a calibrated fan and measures how much air escapes. California requires this test when most new heating and cooling systems are installed or altered, and a HERS rater verifies it. We do that testing; see HERS acceptance testing.
How it's fixed
- Sealing joints and seams with mastic or approved tape.
- Reconnecting or replacing crushed or disconnected runs.
- Replacing old ducts that are beyond repair, often when the equipment is replaced.
If you're planning a new system, the ducts are worth looking at in the same visit. Call us at 805-965-6326 or send us a message.
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