Duct Leakage Testing in California

Licensed & insured Every company we put you through to holds current licensing and insurance.
Know what to ask You are told what actually decides the price, so you can judge a quote.
Someone local You are put through to a technician who works your area, not a call center three states away.
Calls answered 7 days Someone picks up seven days a week, weekends included.

Is it urgent?

Can wait

Never urgent, and almost always worth doing first. It is the cheapest test in this trade and it is the one that stops you buying work you do not need — or proves the work you do need.

Two things override everything on this page. If anyone has symptoms of carbon monoxide exposure — headache, nausea or dizziness that improves outdoors — leave the building and call the gas utility or the fire service, not a duct company. And if you can smell burning while the dryer is running, unplug it and leave it.

Signs to look for

A quote for duct sealing or replacement that was not based on a measurement
Replacing a furnace or air conditioner, where a test may be required rather than optional
Rooms that will not balance however the dampers are set
A cooling or heating bill that does not match the age and rating of the equipment
Buying or selling a house and wanting the system documented

How the work is done

Sealing the registers and pressurizing the duct system with a calibrated fan
Measuring total leakage, and leakage to outside separately, because the second number is the one that costs money
Locating the leaks with a pressure pan or theatrical smoke rather than by guessing
Reporting the result against the applicable standard, and retesting after any sealing work so the improvement is documented

In California specifically

In California the ductwork is generally in attics and crawlspaces, and on slab-on-grade homes in the south often under the floor or in the ceiling plenum, which is most of why this job looks the way it does here. Wildfire smoke is the single biggest thing that makes Californians think about what their ducts are carrying. Fine particulate gets pulled into a return during a smoke event and keeps circulating long after the air outside has cleared. California is also the one state where duct leakage is routinely tested: Title 24 requires a HERS-verified duct test on most furnace or air-conditioner changeouts, so a duct problem here often surfaces as a failed test rather than as a complaint.

Before the technician arrives

Four things worth doing — and the first one is usually the thing people get wrong.

Ask for the number in writing, both total leakage and leakage to outside. A pass or fail on its own is not useful to you.
Book it before any sealing work, not after, so there is a baseline to compare against.
Have the equipment nameplate details available — the standard the result is measured against depends on the system.
Clear access to every register and to the air handler, since all of them get sealed for the test.

What the work looks like

Photographs of duct leakage testing being carried out, so you know what to expect on the day.

How it works

Three steps, and you decide at the end of them.

1
You call and describe the problem

Tell us what you have noticed and where — the room, the smell, the noise, how long it has been going on. Give us your ZIP code and we will match you to a licensed company covering your area. There is no form to fill in.
2
A local company takes it from there

They discuss the problem with you directly, arrange a time to inspect, and agree the work and the price with you before anything starts. That conversation is between you and them.
3
You decide whether to go ahead

You are under no obligation. If the quote or the approach is not what you wanted, you are free to say no and call someone else.

Duct Leakage Testing — FAQs

Do I actually need Duct Leakage Testing done?

Never urgent, and almost always worth doing first. It is the cheapest test in this trade and it is the one that stops you buying work you do not need — or proves the work you do need.

What does Duct Leakage Testing involve?

Pressurizing the duct system with a calibrated fan and measuring how much air it loses, which turns a comfort complaint into a number you can act on and compare quotes against.

What makes this different in California?

In California the ductwork is generally in attics and crawlspaces, and on slab-on-grade homes in the south often under the floor or in the ceiling plenum, which is most of why this job looks the way it does here. Wildfire smoke is the single biggest thing that makes Californians think about what their ducts are carrying. Fine particulate gets pulled into a return during a smoke event and keeps circulating long after the air outside has cleared. California is also the one state where duct leakage is routinely tested: Title 24 requires a HERS-verified duct test on most furnace or air-conditioner changeouts, so a duct problem here often surfaces as a failed test rather than as a complaint.

Are the companies licensed and insured?

Yes. We only pass calls to licensed, insured operators working in California, and you are welcome to ask to see a license number on arrival.

What does Duct Leakage Testing cost?

It depends on the property, the size of the system and what the inspection finds, so we do not publish a price — a figure quoted on a web page is not one the attending company has agreed to. You get a price before any work starts.

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Duct Leakage Testing in California

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