Importance of Attic Ventilation

Proper ventilation is absolutely necessary and vital, not only to the health and well being of every home, but also to every home's occupant. Anyone who has been in an attic knows that attics get hot! If the heat in the attic is allowed to sit there, it will conduct heat into the house, or, at the very least, prevent the heat in the house from escaping. Without adequate ventilation you will encounter problems such as rapid shingle deterioration, mold throughout the attic, wood rot, mildew, peeling exterior paint, rusty nails, energy losses, and other problems are often the direct result of inadequate attic ventilation. Wood boring insects such as Termites and Carpenter Ants are attracted to moisture buildup that is often caused by any inadequate ventilation.

 Ironically, improving ventilation conditions can often be accomplished with low to moderate cost expenditures. Once our clients understand the problems associated with poor ventilation, there is usually a willingness to make these improvements. When there is significant damage from poor ventilation such as delaminated roof sheathing with substantial mold or mildew buildup, improving the ventilation becomes secondary to repairing the damage.


 This is what can happen to your roof shingles, and attic if the ventilation is compromised.


    Factors Affecting Attic Ventilation 

■Lack of under eave soffit ventilation. This is the #1 reason for weather infiltration. There should be an equal or slightly greater amount of free area in the soffit regardless of the type of exhaust system used. Make sure that the soffit vents are not covered by insulation, light should be visible in the soffit area.
■If lanced or perforated soffit panels are used, the ones that provide maximum ventilation should be used. Vented panels should be used continuously around the soffit area. Panels with holes typically have more free area than panels that are lanced. Also, some lanced panels are often not lanced cleanly and can cause more resistance to air flow.
■Do not mix different exhaust products on a single attic, i.e., do not use roof vents with ridge vents, ridge vents with power vents, turbines with roof vents, etc… Avoid using ridge vents or roof vents near gable vents. Depending on wind direction, the gable vents can act as exhaust vents and cause the ridge or roof vents to act as intake vents. If problems occur, make the gable vents non-functional.
■Keep roof vents on the same side of the ridge. Do not place them across the ridge from one another. Depending on the wind conditions, one roof vent may try to feed from the other roof vent.
■Do not use roof louvers on the lower part of the roof for intake. Roof louvers are designed to be exhaust vents and may not offer the desired weather protection when being used as intake.
■Do not use ridge vents on rakes or hips of hip roof designs. Ridge vents are designed to be exhaust vents. When installed on the rakes, the exhaust / intake systems are indefinable.
■Avoid placing ridge vents or roof vents on dormers when dormers are lower than the main ridge and connected to the main attic. If vents are put on lower dormers which are connected to the main attic, separate the dormer from the main attic and let the dormer be a “mini attic”.
■If ridge vents are used on homes with multiple ridge line heights, it may be desirable to separate the attic areas where the ridge lines change. This may be done with plastic sheeting or roofing felt.
■Cut the hole(s) correctly. Holes that are cut too large can lead to weather infiltration. This is especially true for ridge vents since some of the internal baffling may be rendered ineffective.


Website Builder