Duct sealing in Abbeville, GA that is measured, not assumed

What duct sealing does for a home

A forced-air system moves the same air around the house again and again. Every gap along that route changes the balance. Supply leaks push conditioned air into places nobody lives, such as the attic or the space between floors. Return leaks do the opposite, pulling unconditioned air, and whatever it carries, into the system to be heated or cooled and delivered to your rooms.

ENERGY STAR has estimated that in a typical house around 20 to 30 percent of the air moving through the duct system is lost to leaks, holes and poorly connected ducts. Your home may be better or worse than that, which is exactly why we measure before we recommend anything. Sealing is one of the few improvements where the benefit can be shown with a number rather than a promise.

How leakage is measured

A duct leakage test pressurizes the duct system with a calibrated fan while registers and grilles are temporarily covered. The fan reports how much air it must supply to hold a set pressure, and that airflow is the leakage. The same test repeated after sealing shows how much was recovered.

Where a full leakage test is not practical, static pressure readings, temperature loss along supply runs and a careful visual inspection still reveal the worst problems. Smoke pencils and thermal cameras help locate specific leaks at joints, boots and plenums that are hard to see.

The readings are shared with you in plain terms. You will know roughly how leaky the system was, where the largest gaps were and what the second test showed once the work was done.

Where leaks usually hide

The connections at the furnace or air handler are the most common culprits, because pressure is highest there and panels are often left unsealed after filter changes or service. Return plenums built from framing lumber and drywall panning are notoriously leaky and draw air from wall cavities and basements.

Register boots, where the duct meets the floor or ceiling, frequently leave a gap to the drywall or subfloor. Conditioned air escapes into the cavity around the boot instead of entering the room. Sealing boots from inside the room is simple and often overlooked.

Longitudinal seams on sheet metal ducts, takeoffs from the trunk and the joints on flexible duct connections round out the list. In attics and crawlspaces, disconnected branches can dump all of their air into the unconditioned space.

Materials that last

Duct mastic is a thick paste applied over joints and seams, often with fiberglass mesh tape embedded across wider gaps. Once cured, it stays flexible and bonded for many years. It is our first choice for most sheet metal connections.

Tapes are used where they are appropriate, and only tapes listed for duct sealing. Ordinary cloth duct tape, despite the name, tends to dry out and release as temperatures cycle, which is why so many old joints are found with tape hanging loose.

Some companies offer aerosol sealing, which seals leaks from inside the ducts. It can be useful where ducts are inaccessible. We explain when a different approach might fit your house better than hand sealing and help you weigh the options honestly.

Sealing the return side first

Return leaks deserve priority because of what they bring in. A return duct running through a garage can pull in exhaust fumes. One in an attic can draw insulation fibers and superheated summer air. One in a crawlspace can pull in damp, musty air and soil gases.

When returns are tight, the system draws air only from the living space, through the filter, as designed. Many homeowners notice less dust within weeks. If a combustion appliance shares a space with leaky returns, sealing them also reduces the risk of depressurizing that space and disturbing the appliance's venting.

Supply side sealing follows, focusing on the trunk connections and the branches that feed rooms with comfort complaints.

Comfort and equipment benefits

Rooms at the end of long duct runs often improve the most after sealing, because air that used to escape along the way now reaches them. Temperature differences between floors can narrow, and registers that barely moved air may blow noticeably stronger.

Equipment benefits too. With less air escaping, the system reaches the thermostat setting sooner and runs shorter cycles. Airflow across the coil and heat exchanger is more consistent, which supports efficient and reliable operation.

Sealing does not fix every problem. Crushed or badly undersized ducts need replacement, which our Ductwork Install And Replace service handles. The measurements help separate what sealing can solve from what needs a bigger fix.

Insulation after sealing

Ducts running through attics, garages and crawlspaces should be insulated once they are sealed. Insulation reduces heat gain and loss through the duct walls and prevents condensation on cold supply ducts in humid weather.

Existing insulation is inspected and repaired where it has torn, compressed or fallen away. Sealing is always completed before insulation is wrapped, since insulation alone does not stop air leakage.

Where ducts are buried under attic insulation, we take care to restore the insulation depth after the work so the home's thermal envelope is not weakened.

Pricing and what to expect on the day

Duct sealing is priced by scope: the equipment connections, the return plenum, a number of register boots, attic or crawlspace runs, and any testing. The written price lists each item so you can see what is included.

Most homes are completed in a day. Technicians work in attics, basements and crawlspaces with care for insulation, wiring and stored belongings, and inside the home they protect floors near registers and the equipment.

At the end of the visit you receive the before and after readings and a short summary of what was sealed. Keeping that record helps future technicians and can be useful if you ever sell the home.