How Do I Check and Control My Humidity?

Indoor humidity can sometimes be problematic in your home—especially during the Winter months. Ensure your new Excel home is moisture-smart with these simple steps with these simple steps to help control your indoor moisture and prevent mold growth.

Moisture Control in the home is essential throughout the year—not just during the first year as all the building components are trying to dry out. Controlling the humidifier and running the furnace and kitchen fans will help to manage the indoor relative humidity and minimize the risk of condensation.
Respond to any water intrusions and repair or stop water leaks upon discovery
Manual removal of water and ventilation are required to mitigate damages
Respond to any signs of mold growth immediately
Maintain optimum indoor humidity levels between 30% – 40%. During cold weather, optimum indoor humidity levels are between 10% – 20%. we recommend your HRV being set to the 40:20 ratio which will provide 40 minutes of recycled air and 20 minutes of fresh air per hour.
Check your furnace intake and exhaust pipes on the exterior of your home regularly to ensure that they are free of obstruction (ie. remove snow & ice in the winter, etc.).
High indoor humidity levels inside the home will be indicated by moisture and frost build-up on exterior door handles, window glass, window/door frames and possibly within in a HRV (Heat Recovery Ventilator) where installed
Proper maintenance of the mechanical systems is required to ensure optimum performance
Follow the manufacturer's recommendations for proper HVAC (Heating, Ventilation and Air Conditioning) system operation, cleaning and maintenance
Operate your ventilation fans daily—especially critical before, during and after showering or bathing
Make sure that floor vents and basement ceiling vents are open and unrestricted (never close fully). Adjustments of your floor vents can create force changes in airflow. Heat cold spots by restriction airflow in hot spots and un-restricting airflow in cold spots.
Perform regular building inspections watching for signs of moisture damage
Restrict and monitor the usage of additional personal humidifiers, indoor plants, water features and aquariums; these are some of the many contributors to extra humidity in homes
Leave an air gap between your belongings, furniture and exterior wall
Keep items stored in the basement off the floor and away from the mechanical systems
Inspect basement poly for any rips, cuts or tears
Hiring professionals for any future alterations to the original structure is highly recommended
If sharing or leasing any of the structure to others, please communicate these moisture and mold prevention requirements to all occupants
Close your windows and fully open your curtains and/or blinds during the day to help dry the surfaces.
Check your thermostat settings to ensure that the temperature is not running too high or too low.

Here are some other helpful links for indoor moisture management:

Last updated on Mar 28, 2025.