||09-19-2007 12:25 PM
Ventilating Roof with no ridge?
My house has three levels of roofing. One over the wrap around porch, then one over the second floor, and a third level over a single third-floor room. Pitch is 5:12. Each level drains down onto the next one down.
The first level of roof has no heated space under it, so damming isn't a problem. There are no eave vents, and the roof ends against the exterior wall for the 2nd floor, so no place for a ridge vent either. Is it ok that this space is unventilated? Will that contribute to deterioration of the roof on that surface because of summer heating? (The roof is 15 years old, and is in need of replacement on the southern side of that part of the roof.)
The second floor roof has an L that has a continuous ridge vent, and the remainder of the roof ends at the exterior wall of the 3rd floor, so no ridge vent on those sections. However, all areas of the 2nd floor roof have continuous soffit vents. One valley area of the 2nd floor roof is in quite bad shape, and in need of replacement. It's south facing, but close to the ridge-vented area. This deterioration might have as much to do with run-off from the 3rd floor as with any vent problem. (no gutters anywhere)
The 3rd floor roof has soffit vents and ridge vent.
My question is, how should these roof areas with no ridge be ventilated?