By Amanda Veinott

Identify Current Intake Ventilation

Intake ventilation typically occurs along your eaves / gutter edges via soffit vents, an eave-level intake vent like GAF Cobra Intake Pro, or possibly gable vents if your home doesn’t have soffits – like many Cape Cod style homes.

Identify Current Exhaust Ventilation

Exhaust ventilation typically occurs through passive channels like ridge vents, louver vents, or hip vents and active channels like roof-mounted or gable-mounted attic fans. If you have an attic fan, identify if it’s a thermostat-only fan or if it also has a humidity control called a humidistat. You’ll see two dials instead of one if a humidistat is present.

Calculate Proper Ventilation Needed

Utilize GAF’s attic ventilation calculation tool to properly assess your current ventilation needs based on the size of your attic space and the types/sizes/amounts of both intake and exhaust ventilation you currently have.

Address Deficiencies

If you have a lack of intake or exhaust ventilation or if your calculations indicate a deficiency in your ventilation equation, you should make proper adjustments as necessary. If you have a soffit but it’s not vented, you can cut out the soffit wood and install vented vinyl soffit panels. If you have vented soffit panels but no ridge vent and no attic fan, you can have either installed. If your equation indicates an imbalanced ventilation equation, increase or decrease accordingly.

Maximize Efficiency of Current Ventilation

If your attic fan has both a thermostat and humidistat, reference the manufacturer’s recommended settings. They may change in the winter and summer months and should be adjusted accordingly. A rule of thumb is to set your thermostat to 95 degrees and your humidistat to 40%. If you have soffit vents, make sure you have properly installed baffles that push back your attic floor insulation so that as much cool, dry air can flow through the soffits as possible. Blockages by insulation can cause moisture and heat to build up.