During the winter months in Ontario, as a general rule, it is recommended the relative humidity level be maintained between 25% to 40% along with in-home temperatures between 18°C to 24°C.
Daily humidity levels will vary daily depending on activities inside the home and the volatile temperatures outside the house. Cooking, cleaning, bathing and even breathing, all increase levels of vapour in the air.
High levels of humidity will cause condensation, mould, musty smells, allergic reactions and damage to walls and interior finishes.
Low levels of humidity on the other hand, especially in the winter will cause breathing difficulty, sore throat, static electricity and dry skin. Finding a perfect balance can be a little difficult especially in older homes.