One of the most popular segments of our educational seminars is the “Question and Answer” session. That’s when members of our industry can ask whatever is on their mind: roofing contractors, home builders, remodelers, building materials wholesalers, retailers, home inspectors, architects, and even homeowners.

Here are the top five questions asked and answered from our most recent seminar season.

Question #5 is from our seminar in Austin, Texas

"When calculating the number of attic vents needed, do you factor in either the roof pitch or the attic volume?"

Building Code does not factor in either roof pitch or attic volume. However, our calculating tools include three roof pitch ranges to choose from:

1. Up to 6/12 roof pitch in which the number of vents is based on 1/150 airflow ratio (that’s 1 square foot of Net Free Area for every 150 square feet of attic floor space)
2. From 7/12 to 10/12 roof pitch in which we increase the quantity of vents needed by 20% to account for the larger volume in the attic
3. From 11/12 roof pitch and steeper, in which we increase the quantity of vents needed by 30% to account for even more attic volume.

Question #4 is from our seminar in Baton Rouge, La.

"Why wouldn't everyone use an internally filtered ridge vent or attic exhaust vent for an extra layer of weather protection in all climates, not just harsh winter weather?”

People in harsher winter climates tend to recognize the need for the internal weather filter more than those in milder climates, but the filter offers protection in all climates. Internally filtered vents offer an extra layer of weather protection from wind-driven rain, snow, and debris, and the airflow reduction over decades of use is very minimal. There’s third-party testing on our YouTube Channel showing the long-term airflow performance.

To prevent damage from improper ventilation, like the warped shingles seen here, check out the #2 most frequently asked question.
Photo by Air Vent Inc.

Question #3 is from our seminar in Wichita, Kan.

"What's the best strategy to get insurance to stop asking us to reuse the attic vents after a storm because the insurance company says the vents look to be in good condition still?"

Show insurance the Technical Bulletin “Why Ventilation is Important” published by the Asphalt Roofing Manufacturers Association. ARMA is the professional association representing shingle manufacturers. That Technical Bulletin states: "Replace the vents in the field of the roof every time a new roof is installed."

Thus, the various brands of shingles are saying do not reuse the attic exhaust vents with a new roof installation. Explain to insurance, “I’m not supposed to install a new roof with old vents.”

There are many reasons not to reuse the attic exhaust vents in the field of the roof, including damage that can occur to the vents during the removal process. We dedicated podcast episode #48 to this topic: “Do Not Reuse Attic Exhaust Vents.”

Question #2 is from our seminar in Grand Rapids, Mich.

"What should the temperature in the attic be if the attic ventilation is properly balanced 50% intake and 50% exhaust?"

In the winter/colder months, the attic temperature should be as close to the outside ambient temperature as possible to help fight ice dams. This will help any snow on the roof melt uniformly. In the summer/warmer months, the attic temperature should be no more than 20 degrees warmer than the peak outside ambient temperature that day.

Question #1 is from our seminar Raleigh, N.C.

"From a supply chain/distribution perspective, should I start speaking up when I receive orders from roofing contractors or builders for both ridge vents and box vents to be installed on the same roofing project?"

Yes, please speak up. Explain to the customer that if it's a shared/common attic space, avoid mixing different types of attic exhaust vents; otherwise, it short-circuits the airflow and could lead to weather infiltration. Avoid mixing any of the five types of attic exhaust vents: Wind turbines, gable vents, box vents or off-ridge vents, power fans, and ridge vents.

The most efficient way to move air through an attic to fight heat buildup, moisture buildup, and ice dams is to have air enter at the lowest possible location near the eave/soffit and exit high at or near the roof peak with nothing in between. Explain to the customer that the vent manufacturers say, “Don’t mix attic exhaust vents.” The shingle manufacturers say, “Don’t mix attic exhaust vents.” And building code says in section R806 of the International Residential Code, “Ventilators shall be installed in accordance with the manufacturer’s instructions.”