Vented Vs Unvented Roof

Too many people believe the importance of roof ventilation is to increase energy efficiency during the summer.

Vented vs unvented roof.

Control of ice dams moisture accumulation and heat gain can be successfully addressed by both vented and unvented attic or roof design. In coastal climates wind driven rain can be blown in through these openings with similar results. Let s dive a little deeper into what that means exactly. In an un vented roof foam can serve as the air barrier and vapor retarder and prevent moisture from getting in to the roof cavities.

Control construction moisture content with tenting or temporary roofing when necessary. Unvented roof assemblies are not prone to these problems because the ventilation openings have been eliminated. In other words vented roofs may well be the best design for one home while an unvented roof will be a better solution for another home. Vented roofs vented roofs serve a number of different purposes and their roles vary from climate to climate.

A vented attic system refers specifically to having working vents in the attic. In pitched roof construction thermal insulation can be placed horizontally at ceiling level cold roof. Roof vents are for warmer climates. When insulating your attic the contractor can either spray the attic floor to keep a vented attic or spray the roof deck for an unvented system.

In areas subject to wildfires burning embers can be blown in through these openings potentially starting roof fires. In other words the entire vent opening doesn t count as vented space. That said air resistance and interference such as vent grates reduces the area of true ventilation. Basically the term cold roof refers to a traditional roof or vented roof while hot roof refers to a roof that is not ventilated and which has foam insulation attached directly to the roof sheathing.

In this case you can learn a lot from foam tech s article vented vs. In a vented roof foam can seal the openings and serve as an air barrier and a vapor retarder in addition to its insulating function. The choice of the venting approach is up to the designer. Inclined along the line of rafters warm roof or positioned within the roof structure to form an insulated void room in roof which can result in warm and cold roof areas.