Ventilation
As seen in the Milwaukee Area

Home Ventilation
When creating an energy-efficient, airtight home through air sealing techniques, it’s very important to consider ventilation. Unless properly ventilated, an airtight home can seal in indoor air pollutants. Ventilation also helps control moisture—another important consideration for a healthy, energy-efficient home.
Purpose of Ventilation
To ensure adequate ventilation, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) says that a home’s living area should be ventilated at a rate of 0.35 air changes per hour or 15 cubic feet per person per minute, whichever is greater.
Venting and Energy Efficiency
Temperature Differences: Attic and Roof Contributions
Roof Ventilation
When the roof is properly ventilated, it allows air to flow naturally into the attic, and back out again. It also prevents excess heat and moisture to accumulate in the attic, which would lead to the need for a new roof earlier than planned if contained in the attic for extended periods of time.
Having a properly ventilated roof allows your home to breathe. When the excessive temperatures are released from the home instead of into the living areas of your home, it keeps the temperature of the home at a stable level throughout the house. This reduces the need for your heating/cooling system to be used, in turn reducing the energy your home needs to function.