In the climate of southwest Arizona, a residential attic can become a broiling oven just above your ceiling. Summer temperatures in a poorly ventilated attic can easily exceed 150 degrees. In a home with inefficient insulation, studies show that more than one ton of air conditioning volume is wasted just to offset the effect of attic heat on the living space. In addition to energy expense, unventilated attics invite a variety of other problems including deterioration of external paint and roofing materials, as well as infestations of pests such as termites and carpenter ants. In winter, attics with insufficient ventilation can become repositories for wet, humid air that condenses and causes mold, mildew and wood rot. The good news is, attic ventilation can be dramatically improved at modest expense and effort.
Guidelines suggest one square foot of ventilation area for each 300 square feet of attic ceiling space. Air circulates through an attic naturally by utilizing two forces: wind and a “chimney effect.” The best attic ventilation exploits theses forces through the placement of both low and high vents.
High venting normally includes louvered gable vents located below both ends of the house gable. Many houses are constructed with existing gable vents to catch wind. High venting can be enhanced by the addition of vents at the roof’s peak. These may be a low-profile ridge vent running the length of the peak or a number of individual rectangular or round hooded roof vents.
The chimney effect produces the most efficient attic ventilation. It requires the movement of air from a low intake point up to a higher exhaust point such as the gable louvers or roof vents. The addition of aluminum soffit vents, available as round disks, rectangular grilles or long strips, provides a low opening on the underside of the eaves as an entry point for the circulating air. The upward movement creates a natural draft that draws air through the attic space continuously.
Homeowners in the Yuma area are welcome to contact Hansberger Refrigeration and Electric Co. for all of your home-comfort needs. We’ve been family-owned for 60 years.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about attic ventilation and other HVAC topics, download our free Home Comfort Resource guide.
Hansberger Refrigeration & Electric Co services the Yuma area in Arizona. Visit our website to see our special offers and get started today!
Indoor Air Quality image via Shutterstock
