How Much Roof Ventilation

The two main dangers associated with too much ventilation involve roof damage and increased utility bills.

How much roof ventilation. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca. Ventilation can be accomplished using various products and techniques.

The key to proper ventilation of your roof and attic is balance. Many people falsely assume that their roof doesn t require ventilation. Choose one of the following products to meet the recommended intake nfva of 528 square inches. How much ventilation does a flat roof need.

Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed. However we rarely think like that for roofs even though they undoubtedly require ventilation. The amount of space you devote to intake must be equal to the amount you allow for exhaust and these must be calculated according to the size of your attic and slope of your roof. It makes sense as all of us know that the most humid rooms in the house like the bathroom and kitchen need it.

Dangers of too much ventilation. Most building codes require a ratio of 1 150 ventilation space to attic floor space. Allows cool dry air to enter the attic.