Air Vent Inc., a Dallas-based manufacturer of residential attic ventilation products, has been holding its Ask the Expert™ attic ventilation seminars for roofing professionals for nine years. According to Paul Scelsi, the seminar leader for Air Vent, the seminars take place across the country from January through March, and this year the seminar will be featured in the educational track at the International Roofing Expo in Las Vegas on March 8.