There are several common misconceptions about attic ventilation. Many people believe if they have only power vents or turbine vents working near the ridgeline, their attic is properly ventilated. In order for exhaust vents to properly function, they have to have intake vents working with them. Air has to enter somewhere. If there are no intake vents air will enter through some of the other exhaust vents. The result is circulation of only the air immediately surrounding the vents or in between the vents.
Another common misconception is that “more is better.” Many people believe they can improve the ventilation of their attic by installing vents throughout the roof surface. This can cause a “Ventilation Short Circuit.” For instance, if a roof has a full soffit and ridge vent system, and additional vents are installed halfway up the slope, the ventilation is now hampered because air is now exiting out the vents in the middle of the roof before it reaches the ridge, leaving the attic partially un-vented. Depending on wind pressure, air can also be taken in at the intermediate vents reducing the intake at the eaves.
If you suspect you may have roofing damage due to poor attic ventilation, contact Minnesota Building Contractors today. Call 507-206-9607 or submit a free roofing evaluation request.