How do I know if my roof has proper ventilation?

Proper attic ventilation is super important for energy efficiency, preventing moisture problems, and extending the life of your roof. Here are a few ways you can check if your attic is ventilating properly

1. Look for Signs of Poor Ventilation

• Excessive heat in summer: If your attic feels like a sauna, that’s a red flag.

• Condensation or frost in winter: Moisture buildup on the underside of the roof deck can indicate poor airflow. A sign of moisture on the underside of the roof deck is rusty nail tips.

• Mold or mildew: Spots on wood or insulation can signal trapped moisture.

• Roof issues: Ice dams or prematurely aging shingles can also be signs.
  

2. Check for Intake and Exhaust Vents

You generally need:

• Intake vents (usually soffit vents along the eaves)

• Exhaust vents (ridge vents, box vents, gable vents, or turbine vents at the roof peak)

A balanced system (equal intake and exhaust) is ideal. Take a look from the outside and inside your attic to count them.

3. Perform a Smoke Test

This is a DIY trick: on a breezy day, light a smoke stick or incense in the attic and watch where the smoke goes. If it lingers or doesn't move, the airflow isn’t good.

4. Measure Ventilation Area

General rule: 1 square foot of ventilation per 300 square feet of attic floor space (split evenly between intake and exhaust). Check your attic size and vent specs to see if you’re close.