Condensation on the surface of the sealed unit
inside the house is caused by ambient humidity, which must be controlled
compared to the outside temperature. At the beginning of fall, when the heating
system does not function regularly, the water content of the house can vary
around 60%, thus involving a problem of condensation on the interior suface of
the glass. On the other hand, in winter, the ideal water content for the
occupants is between 30% and 50%. A rate lower than 15%, according to the
medical authorities, irritates the respiratory tracts. When the outside
temperature is under -10° C, the water content recommended is 30%.
The
following charter is a good indication of the relative humidity
recommended:
Exterior temperature °C
|
Relative humidity with an
interior temperature of 20°C (68°F)
|
| -30° or less |
No more than
15%
|
-30° to -24°
|
No more than 20% |
| -24° to -18° |
No more than 25% |
| -18° to -12° |
No more than 30% |
| -12° to -6° |
No more than 35% |
| -6° to 0° |
No more than
40% |
Source: CMHC: Canada Mortgage and Housing
Corporation.
www.cmhc-schl.gc.ca