I am a home inspector in So. Oklahoma and noticed a house roof today that does not have any venting near the ridge. It is about 6:12 pitch and mostly hip with two stagered gables projecting at a 90 degree angle from the main ridge which is higher than the gables. The gables cover the garage and have one louver vent on the lower gable. There are about 25 or so soffit vents. The question; Is there code requirements for proper ventilation? There are no ridge vents, turbines gravity vents or powered ventilators. It seems that on a plane equal to the height of the gable louver and above, there is no way for hot air to vent. Is this OK or in violation of some code?
Agreed. Having soffit vents without any exhaust at the top is a recipe for trouble and one of my best souces of business (see my user name).
There has to be an active flow of air thru the attic. If the home is in an are without much airflow or surrounded by trees, I recommend installing active ventilation fans as well as passive. They should be on a thermostat/humidistat control.