Both HRVs and ERVs are mechanical ventilation devices that heat incoming outside air and provide good ventilation for you home. They use air being exhausted out of the home to preheat incoming outside air. ERVs differ from HRVs because they also help to regulate humidity levels in a home. ERVs transfer some of the moisture from more humid air flow to the drier flows of air. Airtight homes located in cold dry climates can sometime be dried out by HRVs. Most BC homes use HRVs for mechanical ventilation.

HRVs and ERVs are recommended for air tight homes that are normally closed up. If your home has issues with moisture and dryness, you should look into getting an ERV to maintain indoor relative humidity levels for your home. But if your home generates a significant amount of moisture (from high occupancy, pets, plants, or frequent cooking) then an HRV may be more appropriate for your home because an ERV may re-introduce too much moisture into your home.

For expert advice on which device is most suitable for your home, consider having an EnerGuide home evaluation and speak to a program-qualified energy advisor.

For more information about HRVs and ERVs, visit Natural Resources Canada and the Heat Recovery Ventilation Guide for Houses.

Did you see a building science or energy efficiency term you did not understand? Check out our glossary.