The Old Ducts are Costing You Money!!
If your home is built before 1980 and you
have high bills or comfort issues this is where to start. Look below and
you will understand that YES, half the cold air
you are buying is ending up in the attic.
If your home has METAL DUCTS this is
the place to start. When these homes were built (before 1980) energy efficiency
was not even on the
list of considerations. I see this everyday and without fail, major comfort
issues are always related to ductwork or the mechanical system.
Who Can I Call?
Call Ken Green at 214-893-1007 He can give an overall evaluation of your ductwork,
Mold and mildew inside insulation on metal duct seam.
Return air duct fallen and letting in hot attic air into the duct system.
If your home has old GREY flex ducts these probably
need to be replaced.
This was the first stab at
flexible ducts. They were a failure. They would eventually diintegrate
from exposure to UV. Now most ducts use the "Silver or Shiny" flex ducts.
Grey Flex Duct Falling apart.
Typically installed between 1975-1985
R-8 Flex properly sealed
with radiant barrier outer sleeve.
How is Duct Leakage Tested?
There is process to test the air leakage
of ducts called a "duct blaster
test". On new highly efficient homes the target is about 2-4% leakage.
On "average" homes with flex duct (the stuff that looks like
slinky's) it is 20% or more and on homes with old metal rigid duct
they often cannot even get
meaning the leakage is over 40-50%. In California they are requiring
duct sealing certification with the replacment of a new AC system. Read
the Requirements HERE
Also, here are some good videos produced by the California
Energy Commission describing the benefits of reducing air duct leakage.
Where Does The Duct Leakage Come From?
Duct leakage is due to several factors:
(Remember, prior to 1980 energy
was cheap, plentiful and nobody really cared about their electric bill).
The main cause is that the connections were never sealed to start.
Also, damage (crushed or separated pipes from 3rd parties doing work in
the attic) or
over the years. Plus, they usually have about a 2 R-value of insulation
resulting in a significant amout of heat gain as the air travels down the
duct to the room.
Broken duct inside insulation.
Customer had virtually no air in these rooms an we just followed
the duct back until we found the "cold spot" and
opened the insulation to reveal broken duct. Notice the dirt
from years of air blowing
into the insulation.
Wet, moldy and stinky. This
leak was typical of every seam on te duct system. The cold
air from the air conditioner duct meets the warm-moist air in the
instant condensation. Just think how much nasty stuff could
be growing in the insulation.
What Does All This Mean?
What this means is that if you have metal or grey flex ducts, then you are
either blowing half the cold air into the attic or could be pulling hot
attic air into
your return ducts.
Before you consider other options, the duct should be address first.
Often customers fix the ducts first, and
air coming out of the vents to drop 10-15 degrees
after the ducts are replaced due to the leak reduction and added
insulation on the ducts. I've seen so many times, I can practically
Remember Duct SEALING and Duct CLEANING are not the same thing. Don't bother
with duct cleaning, it won't help with efficiency.
Reduce Your Electric Usage 50% or More!
When the ducts are fixed AND insulation is added the usage
often drops 30-50% or more, all rooms are more comfortable, and dust
reduced after eliminating the negative pressure from the duct leaks
(which constantly draws air in through all cracks, doors windows,
the air being pulled in is hot and HUMID. Humidity adds extra
heat load into the house. Because of the high humidity, it can be 72
the humidity is low, then It can be warmer and be more comfortable.
Look For Yourself
I've included some pictures below to illustrate just what's going
on BEHIND the insulation once you pull it back. Most people think
keeps the air in, this is NOT true. Notice the discoloration of
the insulation. This is caused by the insulation acting like a
over the years
from the air leaking into or out of the ducts. I've heard it a
hundred times that "I had the ducts checked and the guy said
they were fine". Then, when you pull the insulation back
you see what is included in the these pictures. It's like trying
to stop a leak
with a rag. It just won't work. Some AC contractors would rather
sell you a new piece of equipment rather than fix the real problem
which is the ducts.
Tell a friend or neighbor. Homes with metal ducts (usually built before
and being difficult to keep comfortable. People search desperately
for something that will make a difference, but until the ducts
really have a big impact. Once the realize HALF the cold air
they are buying is
not ending up in their home, then it all makes sense.
If your in the Dallas area give Ken
Green a call at 214-893-1007. Tell him Ed sent you. He is the best duct
Dallas for one reason only...He Cares. There may be some guys
who do it cheaper, but none will do a BETTER job and the results will
for his superior
If you are a contractor in another area and do good work please contact me. I
am always looking for quality contractors.
Advantages of tight air ducts
- Energy / Money Savings
- More even room temperatures and comfort throughout the home
- Better air quality
- Reduction in Dust inside the home.
- Better smelling home without musty attic smell
|Metal ducts wrapped with insulation. The insulation
is usually either foil or white vinyl. The insulation will NOT stop
the air leaks. Remember
the air is under PRESSURE. It would be like wrapping a leaky water
pipe with a rag. It just does not stop the air flow.
|Seam leak (notice mold and moisture) seam was connected with 3 screws
only. This is just ONE seam. A typical home will have 50-100 seams.
|Seam Leak. Notice the two pieces of duct are connected by only three
screws and No tape or mastic.
|Broken pipe (homeowner had comfort issues in two rooms) damage was
INSIDE insulation and was not visible. Once the insulation was opened
up the pipe had been crushed by someone climbing over the large plenum
and using the duct as a foot hold.
|Closeup of broken pipe. Notice the dirt stain INSIDE the insulation.
This is a supply line.
|1965 home - Duct Connection. Notice the gaps around the duct at the
plenum. Since this connection is closest to the blower fan and under
the highest pressure the leakage was probably 20% before air ever got
into the duct. Factoring all the seam leaks along the run the end airflow
was probably less then 30% of original air volume at the start of the
duct run. This room was instantly more comfortable after replacing
|Old duct connections. Notice no Mastic or sealant around connections.
|Duct Elbow Leak - Notice the dark line that lines up with the seam
on the duct elbow. Years of air pushing through this seam has caused
the dark line on each seam.
|Dark stain on return plenum. See next 2 pictures. Behind this dark
spot is big air leak on the return side. This means that hot attic
air is being pulled INTO the air system. Therefore, when the A/C is
needed most on a hot day, the attic is the hottest, and the air being
pulled into the air mix is the hottest. When people say that their
A/C system can usually keep up, but not on a really hot day it is often
a return air leak. This big leak is probably pulling 10-20% attic air
|Partial removal of insulation to reveal separated duct from plenum.
This a Huge leak pulling Hot Attic air INTO the A/C system.
|Full removal of insulation to reveal leak. This ONE Leak was so bad
that just doing a temporary seal on it enabled the home to cool off
5 degrees (from 80 to 75). Once the ducts were completely replaced
the homeowner could cool the home down to 71 degrees on a 100 degree
day without any additional insulation.
|This pictures show how the insulation wrapping the ductwork has become
discolored over the years from dirty attic air being pulled into the
duct. Once it is pulled back a little you can see the "clean" spots
that were folded on the inside.
|Stain around plenum. Notice dark spot is only on the side with a
return air duct. This is caused from air being pulled through the whole
side of the plenum.
|Dirt around can lights - Home under negative pressure due to excessive
duct leakage. Attic air is being pulled through the can lights into
the living space to "make up" for duct leakage. Notice the
dark spot around the can light. The negative pressure and unconditioned
air (dirty attic air) being drawn into the brings excessive dust which
often leads to a very dusty home.
|Home under negative pressure. Notice the "clean spot" below
where the paper was pulled off. This home is pulling air through light
switches and other openings. Imagine how much air must pass through
a light switch over the years to cause the insulation to discolor due
|New R-8 Flex ducts installed properly and sealed with mastic. These
ducts are SEALED TIGHT and with the radiant barrier sleeve and R-8
insulation will greatly reduce the amount of heat gain into the ducts.
Often the air coming out of the new ducts will drop over 10 degrees
compared to the old ducts.
|Properly sealed seams on plenum and air handler. ALL seams must be
sealed for a "tight" duct system.
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