Roof Insulation Vaulted Ceiling Unvented
Install insulation along the underside of the roof deck of an unvented attic rather than on the ceiling deck of a vented attic for either of two reasons.
Roof insulation vaulted ceiling unvented. To provide an unvented conditioned space for locating hvac equipment in the attic and or to provide a continuous thermal barrier for designs that have complex coffered ceiling planes and or numerous penetrations for lights speakers vents. Worries about the hot roof un vented cathedral ceiling designs how to. You could leave the ceiling insulation in place providing some additional insulation for the living space below. The quest for greater energy efficiency in buildings has led to increasing interest and need for insulation improvements in hvac equipment more airtight construction new materials and assemblies.
Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction. As with cathedral ceilings the insulation is in the rafters and or the roof deck. If you want the attic to be conditioned space that is heated and cooled then your best bet would be an unvented cathedral ceiling sometimes referred to as a hot roof. Suggestions for un vented or hard to vent building roof cavities.
How to avoid condensation leaks attic mold insulation mold structural damage to roof framing when roof venting is not possible cathedral roof and knee wall insulation venting air path options in older homes hot roof designs. Martin s post focuses on the marketing of owens corning 039 s propink unvented attic insulation system. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck. An unvented assembly can perform well but it s important to get the details right to avoid sheathing rot.
Unvented attic assemblies code notes 2009 irc 2012 irc. The primary benefit of cathedralized attics is the ability to locate hvac ducts inside conditioned space where. Verify that roof insulation installed under the roof sheathing is well supported. Senior engineer manager at icynene john broniek makes the case for the unvented attic assembly and why insulating the underside of the roof makes sense.
Regarding the roof insulation closed cell foam is the best product to use for an unvented cathedral ceiling.