Vaulted Roof Ventilation

You ll want a tight ceiling air barrier with no air leakage into the cathedral ceiling a critical detail for all cathedral ceiling designs.

Vaulted roof ventilation.

Proper ventilation even with the attic bypasses sealed and effective vapor retarders installed proper ventilation is essential to prevent moisture problems in cathedral ceilings. As much as regular attic ventilation is an important part of your house maintenance routine and usually easy to perform cathedral ceiling ventilation maintenance might be difficult or even impossible to do. In my proposed cathedral ceiling detail sketch at left i want to use a reflective foil between the insulation and the roof sheathing to double as a radiant barrier and a cathedral ceiling ventilation space liner. Without an attic baffle there will not be any air space for fresh air to enter the attic from the soffit vents.

Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. Then insulate below with fiberglass or cellulose add a vapor retarder and your finish ceiling. Depending on your house interior and roof framing design cathedral ceiling ventilation can be treated as an independent or attic ventilation related condition. James french suffern ny.

A ridge vent features an open strip along the length of the ridge where the air that enters the soffit can escape. That is create a vent channel above the insulation with low and high vents. When renovating an older home whose roof rafters are only 2x6 really 5 1 2 x 1 5 in dimension the available space for insulation and ventilation is limited therefore limiting the options for a combination of good under roof ventilation and high insulation r values in the cathedral ceiling. Cathedral vaulted or any ceiling that has insulation blocking the airflow from the soffit vents to the attic needs an attic baffle in each rafter bay.

In a vaulted roof a ridge vent serves as the outtake or exhaust vent. Is the radiant barrier in a useful place. If the attic space is going to be conditioned either for living or mechanical purposes or if a home design calls for a vaulted ceiling provision r806 3 in the international residential code calls for the roof deck above the space to be vented continuously from the eave to the ridge. Vent the roof deck.