Tips & Care

Where surface condensation is evident, humidity level’s should be considered. However, each person has his or her own level of personal comfort and the amount of condensation they are willing to accept, to maintain that level. If the occupants insist on a high level of humidity within the house, surface condensation must be expected when outside temperatures are low.

Some indications of high levels of humidty in the house:

  • Water or ice on windows
  • Frost on door handles and hinges, or door is frozen shut
  • Fungus, mold and mildew growth
  • Damp spots or mildew on walls and ceiling
  • Damp spots or mildew on closet walls
  • Moisture on light fixtures
  • Delaminating of plywood materials
  • Ice or frost under roof sheathing boards


See chart as a rough guide for Indoor Humidity levels

Outdoor Temperature Maximum Indoor Humidity
40 degrees F (4 C) 45% Humidity
32 degrees F (0 C) 40% Humidity
20 degrees F (-7 C) 35% Humidity
10 degrees F (-12 C) 30% Humidity
0 degrees F (-18 C) 25% Humidity
-10 degrees F (-23 C) 20% Humidity