Good attic ventilation helps your roof last longer and can reduce cooling costs and ice dams. Here’s why it matters and what “balanced” ventilation means.
What goes wrong without ventilation
In summer, a hot attic bakes the back of the roof deck and shingles, shortening their life. In winter, warm, moist air from the house can condense in the attic, leading to mold and rot. Poor ventilation also encourages ice dams by melting snow unevenly.
Intake and exhaust
Ventilation works best when intake (soffit or low vents) and exhaust (ridge or high vents) are balanced. Air flows in low and out high, carrying heat and moisture away. Too little intake or blocked vents reduce that flow.
Benefits of good ventilation
Shingles and underlayment last longer. Attic stays cooler in summer, which can ease cooling load. In winter, a cooler attic reduces ice dams and moisture problems. Many shingle manufacturers require adequate ventilation for full warranty.
Having it checked
During a roof inspection or replacement, ask your contractor to check ventilation. They can add or adjust vents to meet code and manufacturer requirements. Don’t block soffit vents with insulation.
Summit Roofing includes ventilation in our inspections and can recommend improvements when we replace or repair your roof.