What Is Air Sealing and Why Is It Important?
Air sealing is simply closing holes, cracks, and gaps where
air can pass into or out of your home. On hot and cold days,
you pay money to run an air conditioner or a furnace to
maintain your home at a comfortable temperature. A house
that leaks air costs more to heat or cool because your system
must work longer to "condition" the air. In addition,
if you happen to sit next to one of those leaks, you are
uncomfortable because the room feels hotter or colder. Sealing
those air leaks will help you maintain your home at a comfortable
temperature all year long and help lower energy bills.
The biggest holes are most often found in the attic and
the basement. Caulk, spray foam, and weather stripping are
the most common materials used for air sealing.
Common air leaks:
High Energy Bills
Diagnosis:
One reason for high-energy bills is an increase in the price
of electricity or heating fuel. However, it is common to trace
high-energy bills to an in-efficient component (windows, heating
and cooling equipment, ducts insulation) of your home or a
failure of one of these components to perform as intended.
It is not always easy to pinpoint the problem, but fixing
it can make your home more energy-efficient and comfortable.
Mold, Mildew, or Musty Odors
Diagnosis:
A water leak or high humidity can lead to mold, mildew, or
other biological growth. Depending on the severity, conditions
can lead to rot, structural damage, premature paint failure,
and a variety of health problems. Water can seep into your
house from the outside through a leak in your roof, foundation,
or small gaps around windows or doors. Water can also come
from inside your house from a leaking water pipe, toilet,
shower or bathtub. High indoor humidity caused by normal activities
of everyday living such as showering, cooking, and drying
clothes, can also be a source of mold, mildew or musty odors.
Indoor humidity levels between 30% and 50% are ideal.
Drafty Rooms
Diagnosis:
Cold air leaking into your house around windows, doors, electrical
outlets, light fixtures, and gaps in corners, can cause rooms
to feel drafty and uncomfortable. As cold air is coming in
through leaks, warm air is escaping through other leaks. The
biggest leaks for escaping air are often found in the attic,
and recessed lights are a common location.
Dust
Diagnosis:
Dust comes from several sources and is difficult to eliminate
completely. Increased dust could be a sign that it is time
to change a dirty furnace or air conditioner filter or vacuum
cleaner bag. Activities that produce dust (such as sanding)
can also be a source an increase. Dust can also be introduced
into your home through air leaks in ducts, or air infiltration
through leaky doors and windows.
Moisture on Windows
Diagnosis:
It is difficult to completely eliminate moisture on existing
windows. Inefficient windows (e.g., single pane with aluminum
frames) or high moisture with inadequate ventilation can result
in condensation, frost, or pools of water on windows and sills.
Moisture in the air condenses when it touches a cold surface.
(The same effect causes a glass of ice tea to "sweat"
on a hot humid day.) Continued excess moisture can lead to
mold, mildew, and deterioration of your windows and sills.
Ice Dams
Diagnosis:
Ice dams usually occur after a heavy snowfall and several
days of freezing temperatures. Warm air inside your home leaks
into the attic and will warm the underside of the roof causing
snow and ice on the roof to melt. The melted water will drain
along the roof, under the snow, until it reaches the cold
overhang. The overhang tends to be at the same temperature
as the outdoors and the melted water will refreeze and form
an ice dam and icicles. The ice dam can cause damage to the
roof, which will result in water leaks to the inside. Frequently
the result will be a water spot on the ceiling under the roof
damage.
Hot or Cold Room
Diagnosis:
Temperature differences of up to three degrees from room to
room are not uncommon, but often one or several rooms are
uncomfortably warm or cold. This condition could be caused
by several factors within your home including inadequate insulation,
air leakage, poor duct system design, duct leakage, unwanted
heating by the sun in warmer months, or a failure in part
of your heating and cooling system.
Cold Floors
Diagnosis:
Although some types of floor coverings (e.g., wood, stone,
tile, or concrete) will naturally feel cold on bare feet,
insufficient insulation or air infiltration could be the cause
for cold floors.
Dry Air
Diagnosis:
Air leaks in your home allow warm humid air to escape and
draw in drier colder air. Dry indoor air can contribute to
dry throat and skin and static shocks. Proper humidity levels
keep furniture and your home from drying out and reduce the
energy use of your heating system because you will feel warmer
at a lower thermostat setting. |
