What a leaky duct diagnosis involves
We start at the equipment and work outward. That means checking static pressure across the air handler or furnace, walking the trunk and branch runs in the crawlspace or attic, and looking for the usual failures: separated takeoffs, tape that gave up years ago, crushed flex, and boots pulling away from subfloor. Where access allows, we pressure test the duct system so the leakage is a number rather than a guess. You get a written summary with photos of what we found and where.
What we check and what we install
We inspect joints, plenums, boot connections, flex runs sagging between supports, and insulation that has fallen off in a damp crawlspace. Return leaks matter as much as supply leaks, since a return pulling crawlspace air brings moisture and dust into the house. Repairs typically mean mastic on joints, mechanical fasteners at takeoffs, new insulated flex where a run has been crushed or torn, and resupporting sagging duct so it stops kinking. We reseal boots at the floor line where most of the leakage hides.
How we decide it is the right call
Duct leakage is worth chasing when the equipment tests fine but rooms do not match, when the system runs long cycles without pulling humidity down, or when the crawlspace smell shows up at the registers. High static pressure with dirty duct interiors points the same direction. If the real issue is an undersized return, a failing blower, or low refrigerant charge, sealing ducts will not solve it, so we tell you that first and price the repair that actually fixes the complaint.
What you get on every job
The quote comes first, in writing
Covering 171 cities across Washington DC, Delaware, Maryland and 5 more.A real person answers
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Carrier, Trane, Lennox, Goodman and more. We are not an authorized dealer for any of them.Leaky Duct Diagnosis — quick answers
How do you know the ducts are leaking and not just undersized?
Static pressure readings and a pressure test tell them apart. Undersized duct shows high pressure with low leakage. Leaky duct shows air loss to the crawlspace or attic, often with visible separations at takeoffs and boots.
Can leaky ducts make my house humid in summer?
Yes. Returns pulling air from a vented crawlspace bring moisture straight into the system, so the AC spends its capacity on outdoor humidity instead of your rooms. Sealing returns usually makes the biggest difference.
Do you have to replace all the ductwork?
Usually not. Most systems need sealing at joints and boots plus a few sections of flex replaced where they are crushed or torn. Full replacement only makes sense when the duct is failing throughout or badly undersized.
How it works
- Step 1
Tell us the symptom
Call or fill in the form and describe what changed. Warm air, short cycling, a smell, water near the indoor unit. Details like that help us load the right parts before we leave.
- Step 2
We diagnose the whole system
We check the thermostat, the indoor unit, the outdoor unit and the ductwork, including runs in crawlspaces where damp air and loose joints quietly cause weak airflow and long run times.
- Step 3
You approve the fix
We explain what failed, what it takes to repair it, and what we would watch next season. Nothing gets replaced without your yes, and we clean up before we leave.
- A real person answers
- Open 7 days
- Written quote before work starts
Why homeowners call us
- Humidity is our home groundMuggy summers and damp shoulder seasons drive most of the calls we take. We look at moisture and airflow together, not the cooling number alone, because a clammy house often means a sizing or duct problem.
- Crawlspace ducts get checkedOlder homes across the region run supply ducts through vented crawlspaces. Crushed flex, disconnected boots and soaked insulation show up constantly, and we get under the house to look instead of guessing from the register.
- Heating and cooling bothSame crew for air conditioning repair in July and heating repair in January. We know how your furnace, heat pump and air handler share ducts and a blower, so one visit covers the whole system.
- Plain talk on repair or replaceWhen a repair makes sense, we repair it. When a system is failing in ways that will keep costing you, we say so and explain why, then leave the decision with you and your timeline.
- All major brands, gas & electricCarrier, Trane, Lennox, Goodman, Rheem, York and more, as an independent company.
- Straight answersIf a system is not worth repairing, we say so, often right on the phone.
Leaky Duct Diagnosis
Ready to book leaky duct diagnosis?
Describe the system and your ZIP. The written quote comes before any work.
- A real person answers
- Open 7 days
- Written quotes
- All major brands
- Gas & electric
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