Air Infiltration into Your Home is Taking Money Out of Your Pocket
Properly insulating your home can save hundreds of dollars a year off of your home heating and cooling bills. However, even before you worry
about insulation, you need to deal with air infiltration. Air infiltration
is about drafts - air leaking into or out
of your home. Your home will never be energy efficient
if it has air leaks. Think of your home as if it were a swimming pool.
If your pool was leaking water, would worry about heating the water you
have to constantly add or would you worry about stopping the leaks. So
it is with your home, you have to stop the leaks first.
You may consider hiring an energy auditor to professionally evaluate
your home. They can help you locate leaks, assess your insulation needs
and provide you with a report that will help you decide what needs to
be done, and where your money is best spent. An comprehensive audit will
help you to reduce your energy bills while improving the comfort of your
home. Even if you don't hire an energy auditor, there are plenty
of things you can do yourself.
Start by Detecting Air Leaks
An energy auditor will conduct a blower door test.
A blower door is a powerful fan that mounts into the frame of an exterior
door. The fan pulls air out of the house, lowering the air pressure inside.
The higher outside air pressure then flows in through all unsealed cracks
and openings. An auditor then can measure the amount of air infiltration
and using a smoke tool, can pinpoint the source of leaks.
If you plan to find the leaks yourself, one method is to wait for a
windy day. A windy day makes it much easier to locate drafts. First,
turn off the heater, air conditioner or any other ventilation equipment.
Close all exterior doors, windows and close the fireplace damper. Turn
on your stove and bathroom ventilation fans. Light an incense stick and
move it near possible points of air infiltration. If the smoke is sucked
in or blown away, there is a draft and it should be sealed. This can
still work without wind, but drafts are more difficult to detect. If
you have a heavy duty fan, you might even be able to rig up your own
blower door test by placing the fan in the door, facing out, and sealing
around it with plastic and duct tape.
Common Points of Air Infiltration:
Wherever different materials meet,
such as between wood siding and brick or between the chimney and the
ceiling, there is the potential for gaps. Also, inspect the following
areas for any cracks and gaps that could cause air leaks:
- Doors - both between the door and the jamb and between the jamb and
- Windows - both around the window frame and between the frame and
- Mail chutes - around the mail chute, also make sure it closes tightly
- Any place where pipes or wires pass through a wall
- Around window air conditioners
- Light switches and electrical outlets, especially on exterior walls
Sealing Your Home
Sealing air gaps will require different materials depending upon the
application. Rubber gaskets are available for switches and electrical
outlets and are installed beneath the cover plate. Caulking can be used
to seal between different materials such as between stucco and wood siding.
Caulking is also useful around exterior door and window casings and where
pipes and wires pass through a wall. Expanding foam may be useful for
filling larger or difficult to access gaps and gaps around around door
and window jambs where they meet the surrounding wall framing.
Sealing air leaks will make your home more comfortable and will result
in lowered energy consumption for heating and cooling. Newer homes
are built much more tightly than ever before and so much attention is
paid to ensuring adequate ventilation. If you successfully seal
your home, you must also implement a ventilation strategy. Indoor air
pollutants can build to unhealthful levels and so proper ventilation
must also provided. Furthermore, homes that burn natural gas, propane,
fuel oil or wood must also make certain that adequate air supply is available
for combustion so that a dangerous back draft condition does not pull
combustion gases back into the home.