Windows with vinyl frames help guard against the damaging effects
of window condensation because of the high insulating value of
the vinyl. Double glazed windows are far more effective than single
glazed windows in reducing window condensation because they tolerate
higher percentages of relative indoor humidity before condensation
occurs. This higher allowable humidity level reduces drying of
furnishings and improves the "comfort level" of the living space.
Windows do not cause condensation. On the contrary, the right
windows can be a great help in controlling and reducing it.
2. What Causes Condensation?
Condensation on windows is an alarming signal of excess humidity
in a home. When water, fog or ice forms on a window, the consequences
can be devastating. Peeling paint, rotting wood and rusted metal
can all result from this excess humidity.
Condensation occurs on windows when warm moist air comes in contact
with the colder surface of the window. Although it is natural
to assume that the windows are to blame, the fact is that the
windows are merely a visible sign that humidity exists in the
home.
Indoor moisture is caused by a variety of factors. Common household
activities such as cooking, showering, running washing machines
and dishwashers -- every activity that uses hot water -- adds
moisture to the air.
Newer homes are more often subject to condensation because they
are constructed with more weathertight materials and methods than
homes built before energy costs were a concern. Weatherstripping,
improved insulation, vapor barriers and modern construction techniques
are designed to reduce air leakage. At the same time, however,
these can act to seal in moisture. Unless provisions are made
to allow this moisture to escape, moisture buildup can result.
3. Can Window Condensation Be Only Temporary?
There are several instances when temporary window condensation
can occur, including:
During showers and baths, cooking, dishwashing and other steam-producing
occasions.
During the start of each heating season. Houses absorb moisture
during humid summers. This will generally dry out after a few
weeks of heating.
During sharp temperature changes. Sudden drops in temperature,
especially during the heating season, can create temporary condensation
problems.
During new construction or remodeling. Building materials contain
a great deal of moisture. When the heat is turned on, this moisture
will flow into the air inside the home. It usually will disappear
after the first heating season.
4. What Can Be Done to Reduce Condensation?
There are many simple steps that can be taken to reduce the humidity
level in the home:
Vent clothes dryers, gas burners, etc. to the outdoors.
Check that all ventilation equipment is adjusted properly.
Use kitchen and bathroom exhaust fans.
Air out the kitchen, bathroom and laundry room during and after
use by opening a window for a few minutes.
Make sure attic louvers remain open all year round and that crawl
spaces are properly ventilated.
Consult a local heating and ventilation contractor to help determine
whether ventilation is adequate and whether it can be improved.
Insure humidifiers are correctly set according to the outside
temperature.
