What is Relative Humidity?
Humidity level both inside and outside your home is expressed by
the term "relative humidity". Relative humidity is the
percentage of water vapor within the air, compared to the total
amount of water vapor the air is capable of absorbing. As an example,
50% relative humidity means that the air is holding half of the
moisture it is capable of absorbing at the present temperature.
At one extreme is 100% relative humidity. If this condition exists
outdoors and condensation occurs, it is raining.
Warm air is capable of absorbing much more water vapor than cold
air. When cold air is heated by your furance, it does not necessarily
lose moisture. You may wonder why air with a high relative humidity
outdoors feels dry indoors after it is heated. This is because the
warmer air can now hold much more moisture than it could when it
was cold. Consequently the relative humidity may have dropped to
an uncomfortably low level. Refer to the relative humidity chart
below to determine the effects on relative humidity when air is
heated to 72 degrees farenheit. There are many benefits
to proper relative humidity. The installation of an Autoflo
whole house furnace humidifier will allow you to add moisture to
heated air, thereby increasing its relative humidity.
| Relative
Humidity Chart |
| Outside Temperature |
Outside Relative
Humidity |
Indoor Relative
Humidity When Air Is Heated to 72ºF |
Recommended
Indoor Relative Humidity |
| -10ºF |
40% |
1% |
20% |
| 60% |
2% |
| 80% |
2% |
| 0ºF |
40% |
2% |
20% |
| 60% |
2% |
| 80% |
5% |
| 10ºF |
40% |
4% |
30% |
| 60% |
5% |
| 80% |
7% |
| 30ºF |
40% |
8% |
35% |
| 60% |
13% |
| 80% |
17% |
|
