By Cass Jacoby.
In your research about ventilation, you will quickly find that it is important to make sure your home’s attic is properly ventilated. You may have your head wrapped around the idea that not all roof vents are the same, but you might be left wondering which vent is best for your roof.
Something you might have come across in your research are the terms “ridge vent, or box vent” which may have left you with some questions regarding what is the ideal roofing ventilation solution for you. Here we unpack what a ridge vent is versus a box vent and if the ridge vent is the right vent for your roof.
A ridge vent is installed at the peak of the roof under the shingle ridge cap and provides continuous uniform exhaust ventilation. For attic ventilation systems to work air needs to be able to enter and exit the attic, providing a continuous flow of air.
According to Marco Industries, the ridge vent is the best type of roof exhaust vent to use when possible.
Because ridge vents are located at the roof’s highest point, they are in prime position to let the hottest air escape the attic space. They run across the entire roof line & have the surface area necessary for expelling large amounts of hot air. They work most effectively with continuous intake soffit vents located at the the bottom of the attic under the eave. Hot air naturally rises and exits the ridge vent and with prevailing winds positive air flows across the ridge of the house creating a negative pressure, pulling air out of the vent and helping to draw in cool air in from the soffits below.
A ridge vent allows for rising hot air to escape the attic, and as a result, your home remains cooler and, according to ENERGY STAR®, the lack of need for air conditioning helps reduce your energy bill.
For these, and other reasons, ridge vents are considered an essential part of most modern roof design.
Florida Roofing Magazine, says that deciding which type of ventilation you should install with your roof is simple. Rather than relying on box vents, end gable vents, wind turbines (also called whirlybirds), or power ventilators, you should follow the U.S. Department of Housing’s recommendation and get a ridge vent. They state “continuous ridge ventilation is the most effective because it is the least dependent upon wind direction and it delivers three to five times more airflow than any other combination.”
According to a Georgia Tech publication on energy-efficient homes, a combination of ridge ventilation and soffit vents is the best, providing even air circulation under any wind condition. The Tennessee Valley Authority agrees, adding that turbine roof vents are the least effective and power vents may use as much energy as they save.
Depending on the amount of exhaust ventilation needed for the attic space and the physical roof design, many homes are great candidates for ridge vents. For example, homes that have an ample amount of ridge line are often properly ventilated using ridge vents. For hip roofs with limited ridge lines, box vents like the Python 65 Slant Back work best.
Python’s four-foot plastic Weather-Tite FlexFit™ Ridge Vent is field adjustable, providing a fit for 12”, 10” and 9” shingle cap sizes and features an exclusive no clog weather barrier that keeps out pests, insects, debris, dust, snow and rain from your attic.
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Cass works as a reporter/writer for RoofersCoffeeShop and AskARoofer. When she isn’t writing about roofs, she is writing about movies for her master's degree and dancing with her plants.