Duct Sealing & Replacement

The usual cause is leakage on the return side of the ductwork, which pulls unconditioned air from the attic or crawlspace into the system. That brings dust and insulation fibres straight past your filter and into the rooms, every time the system runs.

Cleaning removes the debris already sitting in the ducts. Sealing stops unfiltered air being drawn in. If your dust returns within days of a cleaning, sealing is almost certainly what you actually needed, because nothing about how the debris got in there was changed.

It genuinely is after construction or renovation work, following vermin or water intrusion, or where there is visible debris at the registers. It is worth much less on a leaking system, because the ductwork simply refills with whatever the leaks are drawing in.

In most cases yes. Title 24 generally requires duct leakage to be verified by an independent HERS rater when heating or cooling equipment is replaced. The system has to pass before the permit can close, so it is not something a contractor can skip.

For equipment replacement without new ductwork the limit is generally 15 percent, tightening to around 6 percent where the ducts are replaced as well. There is also an alternative threshold based on leakage to the exterior rather than total leakage.

An independent third party certified under the California Energy Commission's rating programme. They test your duct leakage with a calibrated fan and report the result. Independence is the point, since the contractor doing the work cannot verify their own compliance.

The contractor seals them and the system is retested until it passes. That is the process working as intended. It is also why a quote that omits duct sealing entirely is often a quote that has not thought the job through properly.

Frequently yes. Leaking ducts waste the air you paid to condition, pull unfiltered attic air into the house, and leave some rooms uncomfortable regardless of what equipment you have. Those problems exist whether or not a code requirement happens to have been triggered.

Accessible runs are repaired directly with mastic, which outlasts tape by a very wide margin in a hot attic. Where sections are genuinely unreachable, an internal sealing process can be used instead. We will tell you honestly which parts of your system fall into which category.

Most homes are a day, depending on how accessible the ductwork is and how much of it needs attention. We measure leakage before and after, so you get a number showing what changed rather than an assurance that it is better.