Improving Attic Ventilation: Shabby Shingles Plus Soggy Insulation Equals Higher Energy Bills

(HIT) - Does your roof show signs of premature deterioration? Is your attic insulation soggy? Are your energy bills going through the roof? If any of these applies to your home, you may have inadequate ventilation in your attic, according to Marianne Horvat, director of marketing, Air Vent Inc., a leading manufacturer of ridge ventilation products. Fortunately, improving attic ventilation is relatively easy and inexpensive.

"An improperly ventilated attic can cause heat and moisture to become trapped under the roof’s deck which can result in damage to roof structures and shingles," said Horvat. "Moisture build-up on insulation can sometimes lower its energy efficiency—or R-value. Excessive heat trapped in the attic can also cause air conditioners to run more."

In addition to summer heat, trapped attic heat and humidity during the winter can lead to the formation of ice dams, which can be harmful to gutters and shingles. Ice dams occur when attic heat melts snow on the roof and the resultant water flows down the roof and refreezes at the eaves. This ice build-up can distort gutters and expand under roof shingles, leading to premature shingle deterioration. As the ice begins to melt, water can drip onto insulation, making it soggy and ineffective and can leak behind wall cavities resulting in damage to ceilings and walls.

"Many of these potential problems can be avoided by improving attic ventilation. While there are many ventilation systems on the market, a balanced system of soffit and continuous ridge vents provides the most efficient attic ventilation methods according to research and independent testing by Pittsburgh Testing Laboratories.

Soffit vents, installed under the eaves of a home, provide an inlet for air flow. Ridge vents, installed across the entire roof’s peak, or ridge, supply an outlet for air flow. This air pattern provides a continuous flow along the roof undersheath to the ridge. According to Horvat, this system aids in reducing heat build-up and excess moisture, and helps to keep the roof deck temperature uniform. And because ridge vents help keep roof decks cool in the winter, they help prevent ice dams.

When combined with soffit vents, Air Vent’s Shinglevent® II and Multi-Pitch Filtervent® are systems that work efficiently at all times, regardless of wind direction or climatic conditions, according to Horvat. An external wind baffle is built into their construction which allows for air to be actively expelled from attics. In addition, they feature a patented weather filter providing a more complete barrier against weather and insect infiltration, a common "side effect" of some other attic ventilation systems.

"Perhaps most appealing to homeowners is the aesthetic appeal Air Vent ridge ventilation products provide compared with other systems, such as roof or turbine vents," said Horvat. "Ridge vents blend naturally with the roof line, and from the ground, they are virtually invisible."

Multi-Pitch Filtervent is a metal ridge vent with a versatile design that can be used on a wide range of roof pitches to help improve attic ventilation.

Shinglevent II is a shingle-over style of ridge vent (which means the vent is covered with shingles so it can blend in with the roof material) is intended for most shingle-over applications. Both products come with a 30-year limited, transferable warranty and are available in a number of colors.

Ridge vents can be installed over an existing roof, but the ideal time to install a ridge vent is when you are re-roofing your home or adding a room, especially since most roof shingle manufacturers require a home be properly ventilated to validate the shingles’ warranty.

Another time to consider improving attic ventilation is when you add attic insulation, because this often can change air flow patterns and may render existing venting ineffective.

In addition to Multi-Pitch Filtervent and Shinglevent II, Air Vent offers a variety of vents for specialty applications like tile roofs, cedar shakes and dimensional cap shingle applications. For homes not already equipped with a proper air intake system, Air Vent also offers a variety of soffit vents, a drip edge vent and foundation vents.

For more information about improving attic ventilation, visit Air Vent online at www.airvent.com.

Courtesy: Home Improvement News and Information Center