Attic ventilation is not something most New Orleans homeowners think about until something goes wrong — mold on the rafters, shingles curling from underneath, or an energy bill that makes no sense. But in a city where summer humidity regularly tops 75% and afternoon temps push past 90 degrees for months on end, what happens inside your attic directly affects how long your roof lasts. Big Easy Roofing sees the results of poor attic ventilation on roofs across Orleans Parish, Jefferson Parish, and Metairie every week.
The short version: your attic needs steady airflow from the eaves to the ridge. Without it, heat and moisture get trapped, and they destroy your roof from the inside out. Here is why it matters and what to do about it.
New Orleans is not Denver or Chicago. Our climate is subtropical — hot, wet, and relentless. During summer months, an unventilated attic in the New Orleans metro can hit 150 degrees or higher. That superheated air bakes your shingles from below while the Louisiana sun bakes them from above. The result is premature aging — shingles that should last 20 years giving out at 12 or 13.
Then there is the moisture. Gulf of Mexico humidity does not stop at your roof line. Warm, moist air rises into the attic from the living space below (through ceiling fixtures, attic hatches, recessed lights, and bathroom exhaust fans that vent into the attic instead of outside). Without ventilation to move that moisture out, it condenses on cooler surfaces — rafters, decking, nails — and you get mold growth and wood rot.
In drier climates, you can get away with marginal ventilation for years. In New Orleans, it catches up fast.
Proper attic ventilation is based on a simple principle: cool ai
By Big Easy Roofing 
Apr 5, 2023