Are Attic Vents Necessary

Ideally half the vents should be located in the soffit at the bottom of the roof and half in gable or ridge vents near the top to allow for natural circulation of air through the attic.

Are attic vents necessary.

Rafter vents come in 4 foot lengths and 14 1 2 and 22 1 2 inch widths for different rafter spacings. The general rule of thumb on the amount of total attic vent space needed is to have at least one square foot of vent space for every 150 square feet of attic area. Hot air exhaust vents located at the peak of the roof allow hot air to escape. Intake vents located at the lowest part of the roof under the eaves allow cool air to enter the attic.

Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca. In a properly designed passive system air enters through the soffit. The ventilation that controls moisture from condensation and regulates the temperature in your attic relies on air circulation. Of course you try to make the attic scuttle hole use air tight trim on your ceiling cans but it would be foolish to ignore the benefits of a reasonably powered attic fan working in.

Most effective ventilation uses a ridge and soffit continuous ventilation system but even these designs can vary from roof to roof. Advantages of proper roofing ventilation. Does an attic with a metal roof need vents. Before we explore how to ventilate an attic space it is prudent to understand how much ventilation is needed.

Static vents with no moving parts perform as effectively on a metal roof as they do on a shingled roof. Soffit vents may leave air trapped at the top of your attic. Static roof line vents are effective for ventilation but generally aren t recommended due to issues with leaks. The installation of roof vents is a crucial part of roof design because it allows for proper attic ventilation which may help prevent condensation and early aging of your roofing materials.

Metal roofs do not stop moist warm air from rising through the house and into the attic. Rafter vents ensure the soffit vents are clear and there is a channel for outside air to move into the attic at the soffits and out through the gable or ridge vent. Attic ventilation fans help cool air your attic by pushing out the stifling hot air from inside the attic and bringing in cool air from outside. Roof vents and power roof vents are made to work in conjunction with vented soffits so that outside air will replace superheated attic air during hot summer days.