Condensation
Condensation is described as the process that occurs when water vapour in the air is changed into liquid water on a cool surface. Air can hold only a certain amount of water vapour at any given temperature. Condensation will occur if the air temperature is lowered by a surface that is cooler than the air's maximum water-vapour holding capacity.
When condensation appears on your windows, the immediate thought is that the window performance is inadequate. In reality, the culprit is not improperly installed or leaky windows. Your windows are an indicator of humidity in your home. If you notice humidity forming on your windows, maintain and manage the relative humidity inside.
Interior surface condensation can appear on many different cool surfaces in your home, such as toilet tanks, cold water pipes, door hinges and windows.
Table 1 shows the maximum recommended relative humidity for varying outside temperatures. The chart shows that as the outside air temperature drops, the relative humidity must also drop to minimize condensation. Improved ventilation will also assist in reducing the amount of condensation, by increasing the temperature of the cold surface.
Sources of Moisture
The principle sources of moisture in a typical home are the household activities which vary with the living habits of the family. Some idea of the quantities of moisture released by these activities in a family of four is given in table 2.
These figures show that approximately 7 to 9 liters of moisture per day may be introduced into a house with four occupants under normal living conditions. This level can increase to as much as 18 to 23 liters per day on wash days. This may also be increased considerably by an efficient humidifier. Moreover, when gas from a kitchen range is burning or a dishwasher is in use, moisture will be added to the air. Note: watering a large number of plants can also create a lot of moisture in the air.
How to control & Improve ventilation
1. Leave blinds and/or drapes open as wide as possible at night and open all window coverings during the day. This will increase the warm air circulation over the cool surface and increase the temperature of the glass.
2. Check the furnace filter and replace if dirty. A clean filter will ensure maximum flow.
3. Turn your humidifier off during the winter and anytime the temperature falls below 0 degrees C.
4. Always turn on the bathroom fan when bathing or showering. Humidistat controlled fans which automatically turn on when the humidity exceeds the setting on the switch is also available. Running the fan will also reduce the fogging of bathroom mirrors.
5. Always turn on the range fan when cooking.
6. Ensure fresh air intake for the furnace is free of all blockages. If your house has no fresh air intake to the furnace, have one installed.
7. Ensure all hot and cold air registers are clear of any obstruction as this could affect maximum air circulation.
8. Install ceiling fans in locations where heat registers are not located close to the windows. The increase in air flow will help reduce condensation on these windows. Ceiling fans should be run continuously in houses where the relative humidity is above recommended levels.
9. Floors wet from mopping can add large amounts of moisture. Run exhaust fans while floors are wet and avoid washing floors on cold days.
10. Wipe up any excess snow or moisture tracked into the house. The evaporation of the moisture will result in an increase in the relative humidity level.
11. Run your furnace fan continuously. Most furnaces are equipped with a switch which allows the furnace fan to operate even when the furnace is not producing heat.
12. Open doors and windows periodically to allow the dry air outside to replace the moist air inside.
13. Remove interior screens in the winter to allow for better ventilation over the window surface.
Condensation can be an early visible warning that the relative humidity in your house is too high. Following the above steps should ensure that the humidity level is balanced to provide comfort for the occupants, as well as reducing the risk of moisture damage to the house, and condensation on the windows.
**Please Note: Laebon Homes is not responsible for replacing damaged window casing or baseboards due to water running off areas affected by condensation. Homeowners are responsible to mitigate any damage. It is considered Homeowner maintenance to ensure condensation is wiped up as necessary and cloths on window sills are wrung out as needed.