House Roof Ventilation Design

Vent roofs with steeples towers or cupolas can be found in different buildings from barns to cathedrals.
House roof ventilation design. A good ventilation system should be energy efficient prevent unwanted moisture and be cost efficient in direct relation to the size of your house. Roof system ventilation is required by the model building codes such as international residential code irc which includes irc r806 roof ventilation that requires ventilation for attics and cathedral ceilings and icc r905 1 requirements for roof coverings that requires builders to follow the manufacturer s installation instruction. Good roof ventilation can do this but shingle color sun exposure and insulation are exponentially more important to overall energy efficiency than ventilation. While designing the roof it is essential to choose the right number of intake and exhaust vents.
Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator. Ventilation openings shall have a least dimension of 1 16 inch 1 6 mm minimum and 1 4 inch 6 4 mm maximum. The goal of roof ventilation is to get fresh relatively cool air into the attic and vent out hot moist air. And since hot air rises and is exactly what you want to vent out of your attic exhaust vents should always be installed at or near the top of the roof.
Roof ventilation in a cold climate vents moisture and ensures a cold roof temperature to avoid ice dams. Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. It comes on an easy to install flexible mesh roll and is hand nailable with no complicated fitting wrapping nail gun adapters.
Sure installing roof vents for older homes can reduce your hot air during the summer but there are probably more low risk cost effective ways to increase your home s energy. The right balance of intake and exhaust vents can enhance the life of the roof system and improve energy efficiency. The shape of your roof square footage and the climate where you live all contribute to the type of roof ventilation system needed for your tiny home. Roof vents comprise intake and exhaust vents that permit free movement of the air in the ventilation spaces.
The building codes and building science for natural roof ventilation however only appeared in the 1940s.