Pioneer Builders Supply

Roof Ventilation

What is ventilation?

Ventilation provides a continuous supply of outside air into the attic space of a home. The formula for each homes ventilation needs is based on attic space square footage and correct installation of ventilation products. Proper ventilation dictates that 50% of the intake ventilation is placed near the lower attic space and 50% exhaust ventilation is placed near or at the roof peak. Lomanco provides an online Vent Calculator.

Why should a roof be ventilated?

There are many important reasons. To fight heat and moisture, homes in all climates need ventilation all year. Heat in unventilated attics can reach 150 degrees. This intense heat can cause damage to shingles, roof sheathing and radiate down into the home. Moisture can be another problem for homeowners and can cause rot, mildew, mold, paint blistering and negatively affect the performance of insulation. Nearly 50% of homes show visible signs of improper ventilation.

Proper ventilation can reduce heating and air conditioning bills, reduce winter ice build up and help to eliminate mold and mildew which can lead to health problems. It also extends the life of shingles, insulation and other building materials.


Roof ventilation provides homes with the fresh air needed to protect it both inside and out. Since 1976, Cor-A-Vent has been a leader in the attic ventilation market.


Lomanco has been producing quality ventilation products for 80 years. They focus on their products having the correct emphasis on Net Free Area, weather protection and longevity. Lomanco offers limited lifetime warranties on many of their products and a forever guarantee on their Whirlybird turbines.


The roof of a home needs to breathe in to breathe out. Just exhausting the air isn't adequate. There needs to be enough air that enters through the eaves to create a balanced system. Quarrix roof ventilation products ensure a proper ratio of intake and exhaust, which extends the life of the roof.