Interior Condensation
What Is Interior Condensation?
Is your glass “sweating” – is water beading or ice forming on the inside surface of your windows? Don’t be too quick to blame the windows! There’s a good chance that what you are seeing is condensation, a sign that there is excess humidity in your home. Humidity – water vapor mixed with air – is drawn to the coolest surfaces, such as your window. Cool air cannot hold as much moisture as warm air, so windows and doors often collect this moisture and make it visible. A surface that is cooler than room temperature is more likely to show condensation.
What Causes Interior Condensation?
Indoor moisture is caused by a variety of factors, including cooking, showering, running dishwashers, storing firewood, pets, fish tanks, plants, clothes dryers that are not vented properly, even breathing. New windows are more likely show condensation than old ones because they are more airtight – less air is entering your home from the outside. The air leaking from older windows evaporated the moisture before it could collect. While some humidity is necessary for health and comfort, chronic and excessive condensation should be tipping you off to take some action before serious, costly damage, such as decay, mold, paint problems, and even major structural damage occur.
Temporary Interior Condensation
There are several ways to tell if the condensation on your windows is temporary. Does condensation usually form:
Problem Interior Condensation
Excess moisture in your home may eventually cause problems. It may be time to take action if you notice the following signs in your house:
Condensation & Health
Improper temperature and humidity can cause comfort and health concerns. Warm, humid environments encourage the growth of molds and fungi, which can lead to allergic reactions. Dry environments can irritate sinus linings and can progress to a sinus infection. The best way to combat this is to achieve the appropriate balance of temperature and moisture in your home.
Reducing Interior Condensation
Now that you know the what and why of condensation, it’s time to learn how to reduce the conditions that cause it, especially if you are concerned about the effects of that excess moisture on your home and health.
There are several steps you can take in three main areas:
1. Reduce Moisture Sources
2. Increase Ventilation
3. Increase Air Temperature
What Is Interior Condensation?
Is your glass “sweating” – is water beading or ice forming on the inside surface of your windows? Don’t be too quick to blame the windows! There’s a good chance that what you are seeing is condensation, a sign that there is excess humidity in your home. Humidity – water vapor mixed with air – is drawn to the coolest surfaces, such as your window. Cool air cannot hold as much moisture as warm air, so windows and doors often collect this moisture and make it visible. A surface that is cooler than room temperature is more likely to show condensation.
What Causes Interior Condensation?
Indoor moisture is caused by a variety of factors, including cooking, showering, running dishwashers, storing firewood, pets, fish tanks, plants, clothes dryers that are not vented properly, even breathing. New windows are more likely show condensation than old ones because they are more airtight – less air is entering your home from the outside. The air leaking from older windows evaporated the moisture before it could collect. While some humidity is necessary for health and comfort, chronic and excessive condensation should be tipping you off to take some action before serious, costly damage, such as decay, mold, paint problems, and even major structural damage occur.
Temporary Interior Condensation
There are several ways to tell if the condensation on your windows is temporary. Does condensation usually form:
- During baths and showers, cooking, dishwashing, laundry, or other steam producing occasions?
- During the start of each heating season? Houses absorb moisture during humid summers. This will 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.
- 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.
Problem Interior Condensation
Excess moisture in your home may eventually cause problems. It may be time to take action if you notice the following signs in your house:
- Condensation remains on windows throughout the day, even when the outside temperature has warmed up.
- Condensation is forming and running down the walls. It may also be causing discoloration, staining, peeling wallpaper and blistering paint.
- The air smells musty – this could indicate mold, mildew, or in the worst cases, rot – or odors from everyday household activities that linger too long. Odors increase in intensity with high relative humidity.
- Mold, mildew, rot and/or decay are visible. Mold and mildew thrive in most areas and can cause health and house damage.
Condensation & Health
Improper temperature and humidity can cause comfort and health concerns. Warm, humid environments encourage the growth of molds and fungi, which can lead to allergic reactions. Dry environments can irritate sinus linings and can progress to a sinus infection. The best way to combat this is to achieve the appropriate balance of temperature and moisture in your home.
Reducing Interior Condensation
Now that you know the what and why of condensation, it’s time to learn how to reduce the conditions that cause it, especially if you are concerned about the effects of that excess moisture on your home and health.
There are several steps you can take in three main areas:
1. Reduce Moisture Sources
- Stop or severely limit the use of humidifiers, or adjust them to the appropriate setting.
- Limit plants, aquariums, and pets. If you care for a lot of plants, group them in one sunny room and avoid over watering.
- Have your gas appliances checked, if you have not recently. Malfunctioning gas appliances can deliver excessive water vapor into the air along with more dangerous contaminants. Be sure you have a carbon monoxide alarm.
- Store firewood outside.
- Eliminate plumbing leaks.
- Don’t air-dry clothes indoors.
- Correct grading and drainage problems around exterior of your home.
2. Increase Ventilation
- Open windows for a few minutes each day, particularly after steam-producing activities such as showering/bathing, laundry, and cooking. Heat loss will be minimal.
- Run kitchen, bathroom, and other fans longer and more often.
- Improve or add a ventilation system in your home. Ensure that everything vents to the outside.
- Open blinds and drapes. Heavy window coverings restrict the flow of warm air over the interior glass surface.
- Operate ceiling fans to improve air circulation.
3. Increase Air Temperature
- Raise the temperature inside the house.
- Insulate under the seat and over the head of bay, bow, and garden windows to keep window area warmer.
- Direct warm-air supply ducts toward windows or even use a fan for increased air circulation at windows.
