We smoke test ducts to identify and seal observed
The Duct Smoke Testing Process
To ensure that smoke testing is adequately
implemented the following protocol has been established
and should NOT be deviated from:
1. All boots are temporarily sealed by either the AC
Contractor or authorized Smoke Testing personnel.
2. Portable Smoke Tester is connected to the supply and
return sections of the duct work. All dampers, if
installed, to be verified open by AC Representative.
3. AC Representative is present during Smoke Testing to
seal observed leakages with approved materials. Marking
area with spray paint or by other means is not
acceptable as it is the job of the Smoke Testing
personnel to verify that all leaks have been sealed or
4. Smoke Testing personnel notes severity and location
5. Smoke Testing personnel verify that all leaks have
been sealed at rough-in and supply certificate to client
attesting to that fact with date and signature of
certified Smoke Tester.
SPECIAL NOTE: We do not "Sample" any of the
homes that we are under contract. "Sampling"
involves perhaps testing only 1 out of 7 houses (Energy
Star and other programs), and inferring that the other 6
meet the guidelines set forth of that 1 home that was
tested. Our experience indicates that "Sampling"
is a very bad method and have found significant failures
within a batch of homes that would not have been
identified by the sampling protocol. In fact, it
is very rare that we do not find failures after 3 or 4
houses. Buyer Beware. We test EVERY house,
because our reputation depends on providing a quality
Smoke Testing Ducts for
Identification and Sealing of Observed Leaks
A Simple, Obvious & Cost Effective Measure
Energy Conservation that you can See
Duct leakage into unconditioned spaces can cost you
hundreds of dollars per year in cooling and heating
costs. Unfortunately, many of the State and National
energy programs do not adequately address solving this
problem, but only report leakage belatedly. We have
developed a system whereas the duct system is tested and
sealed prior to drywall and insulation installation.
Since duct leakage is invisible, we introduce theatrical
fog in the duct-work at low pressure to visually
identify duct leaks to be properly sealed by the AC
technician with the appropriate materials.
Final duct testing of the house after drywall and
insulation is too late to access the leakages once
entombed above drywall and insulation, leaving the
homeowner with 20 to 30+ years of high cost air
conditioning and heating lost into the attic or garage.
A recent study by the Florida Solar Energy Center (FSEC)
on 30 new construction houses revealed cooling losses of
10-20% in the duct-work alone. Extrapolating this into
monthly costs based upon 10,15, and 20% yields immediate
You expect the plumbing to be pressure checked prior to
occupancy. Doesnt it make sense to have your duct
systems smoke tested by a 3rd party before it becomes
entombed? The cost of the test is minuscule compared to
other energy savings measures and is the cheapest
one-time insurance policy that your system will
operate leak-free for the lifetime of the duct-work.
Contact Us for more
Duct Leakage Testing
Is There a Thief in Your Ductwork? -
From: The Energy Conservatory
There are more than a million miles of duct work in U.S.
homes. And industry experts estimate that more than
two-thirds of them are leaky enough to justify sealing
or repair. Leaky ducts can significantly increase air
conditioning and heating bills, dramatically reduce
equipment capacity and performance, as well as result in
potentially dangerous indoor air quality problems. In
fact, duct leakage is responsible for many of the
comfort complaints experienced by homeowners today.
Why Is Duct Leakage Important?
Leaks in forced air duct systems are now recognized as a
major source of energy waste in both new and existing
houses. Studies indicate that duct leakage can account
for as much as 25% of total house energy loss, and in
many cases has a greater impact on energy use than air
infiltration through the building shell.
Just as important, duct leakage can prevent heating and
cooling systems from doing their job properly, resulting
in hot or cold rooms, and humidity problems. Worse yet,
duct leaks can create air quality problems by pulling
pollutants and irritants directly into the house.
Here are just a few of the problems resulting from duct
Leaks in the supply ductwork cause expensive conditioned
air to be dumped into the attic, crawlspace or garage
instead of into the house.
Return leaks pull outside air (hot in summer, cold in
winter) into the duct system reducing both efficiency
and capacity. In humid climates, moist air being drawn
into return leaks can overwhelm the dehumidification
capacity of air conditioning systems causing homes to
feel clammy even when the air conditioner is running.
Heat pumps are particularly susceptible to comfort
complaints from duct leakage, especially during the
heating season. Duct leaks can cause the air coming from
heat pumps to feel luke-warm or even cold during the
winter. In addition, leaky ductwork has been found to
greatly increase the use of electric strip heaters in
heat pumps during the heating season.
Leaks in return ductwork draw air into the house from
crawlspaces, garages and attics bringing with it dust,
mold spores, insulation fibers and other contaminants.
Household depressurization from duct leaks and
imbalanced duct systems can cause spillage of combustion
products (from furnaces, water heaters and fireplaces)
into the house.
Smoke Testing Frequently Asked Questions
1. Why should I have my ductwork smoke tested?
Answer: Ducts leak...Leakage is
invisible....smoking is the only method to adequately
identify the leakage to address the failures.
2. Is the smoke hazardous to your health?
Answer: No, actually it is not smoke at all, it
is theatrical fog...but "fogging ducts" just doesn't
sound cool. Fogging fluid is heated to the vapor point
and moved through the duct system at a slight pressure.
We have inhaled the stuff with no effects, however we
must confess that we have never drank the fluid straight
out of the bottle.
3. Why isn't it a requirement that all ducts be smoke
tested and repaired by the building code?
Answer: Good question. Even the AC contractors
think that it is a good test because they are called
back for complaints, in the summer, to climb into a 135
degree, unlit attic. Building Officials also realize
that this is a superior test compared to plain visual
inspection. There are many efficiency programs created
by numerous entities with their own fiefdom to protect.
Some are "energy efficient" in name only with little
interest in proactively addressing problems.
4. Is smoke testing required in other states?
Answer: California requires smoke testing in
change-outs of the HVAC system in certain circumstances,
although the process and tools seem cumbersome. The
requirement can be found at:
5. Do you smoke test every house that you have
contracted for or only random, sampled homes?
Answer: We do not know how it is possible to
address failures by testing only X number out of so many
houses. We cannot understand how an energy efficiency
label can be assigned to a home that has never been
inspected or tested, as some "energy-efficiency"
programs do. We have a word for this practice:
No, we do not sample homes as it is our experience that
the number of failures precludes any possibility of
6. Are duct leaks fixed during smoking of the
ductwork or marked with spray paint for the AC
contractor to fix later?
Answer: Just marking the failures doe not
guarantee that they will be fixed later or that we can
even mark the point of leakage adequately. We require an
AC representative on-site, during testing, to
immediately repair failures in the duct system.
7. How do I know if my ducts have been smoke tested
Answer: A certificate is issued by a certified
duct and smoke tester. To ensure that the system has
been tested and sealed by our protocol, the certificate
will be signed by either Bill Eberle or Jon Klongerbo.
8. What is the expected duct leakage reduction by
have a smoke tested performed and failures repaired and
how much will be saved in energy costs?
Answer: That would largely depend upon how bad
the ducts leaked prior to repairing. If there was
initially very little leakage, then the savings/payback
for the test would be longer. If the the system was very
leaky, the payback would be extremely quick. From our
experience, a 30% reduction in leakage can be expected.
Remember, the test and remediation is performed prior to
air handler, insulation, drywall and register
installation and any other factors. Even small duct
leakages at a long period of time can be significant.
9. Why don't you smoke the system after all
components of the AC system are installed?
Answer: After all components are installed, it is
nearly impossible to access what is the major portion of
the distribution system for adequate repairs.
10. My builder/AC Contractor claimed that my duct
system(s) do not leak, why should I not believe them?
Answer: Trust, but verify. If they are so sure
that there is no leakage, there should be no problem in
verifying the claim. It is a relatively cheap insurance
policy that the duct system is smoke tested to be
leak-free. In any event, the claim should be questioned,
since leakage is invisible even to the best of
11. Won't an Infrared camera find duct leaks?
Answer: An infrared depends on a difference of
temperature to be of use. At duct rough-in stage, there
is no temperature difference between the air flow
created by the smoke testing unit and the outside air.
In addition, the infrared camera would require the
operator to give verbal directions to the AC technician
of where the leaks are located, even if it was possible
to locate the failures.
12. How do you know that the duct system is sealed at
rough-in after smoke testing and remediation?
Answer: When no smoke is detected penetrating the