Unvented Cathedral Ceiling Insulation

Regarding the roof insulation closed cell foam is the best product to use for an unvented cathedral ceiling.

Unvented cathedral ceiling insulation.

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. Cathedral ceilings provide a majestic crown for many a great room but insulating them can be tricky. If you choose sistering 2x10 s then they have a net depth of 9 1 4. 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.

Therefore leaving about 1 for venting the net depth of insulation should be about 8 or so. Martin s post focuses on the marketing of owens corning 039 s propink unvented attic insulation system. Our summers in northern california can be pretty hot amp i am looking to add more insulation to my attic the attic floor is insulated already there is a ridge vent there are 2 gable vents 1 has a fan there are 2 between rafter vents. A poorly detailed cathedral ceiling can lead to energy losses and rotted roofing.

Insulating an unvented cathedral ceiling. If installed properly it will create an effective air and vapor barrier to keep interior moisture away from the roof sheathing where it can condense and cause problems. So your choices are 3 1 2 thick batt insulation for an r value of about r 11 9 or rigid insulation board for a r 20 to r 30 depending on the type of board. These assemblies are created by eliminating ventilation openings and moving the thermal moisture and air control boundaries to the plane of the roof deck.

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. In this article senior editor martin holladay describes eight ways to get a cathedral ceiling roof to r 45 or better using both vented and unvented. Yes unvented roof assemblies can be insulated with fiberglass a wufi post and not just in climate zones 2b amp. Unvented roof assemblies such as conditioned attics and unvented cathedral ceilings are becoming common in north american construction.

Worries about the hot roof un vented cathedral ceiling designs how to.