It is important to always use ridge venting. These usually involve special proprietary pieces or the use of commercially available ridge venting products. Many vertical-seam products are vented through the use of specially formed closure strips that allow airflow between the high ribs of the roof panels. Eave soffit vents are used for air intake. Many people have a misconception that installing a metal roof system increases the need for attic ventilation. In fact, with conventional construction, attic ventilation is critical regardless of the roofing material. A metal roof system does not alter the need for proper attic ventilation.
The important thing to remember at all times is that the cause of condensation is warm moist air contacting a cool surface. The goal of attic ventilation is to eliminate the opportunity for that to happen.