Cathedral Ceiling Insulation Detail

Insulating cathedral ceilings can be quite challenging.

Cathedral ceiling insulation detail.

A cathedral ceiling is a sloping and pointed ceiling which is usually high and open. The new workshop will be located over my garage in an area that was framed using attic trusses when we built the new house. That is create a vent channel above the insulation with low and high vents. Attic trusses typically have a sloping ceiling.

You ll want a tight ceiling air barrier with no air leakage into the cathedral ceiling a critical detail for all cathedral ceiling designs. Cathedral ceilings are a feature in many homes that add to value to the house because the high ceiling tends to make rooms look larger. While fiberglass insulation is an excellent and effective product for insulating most building cavities in areas where there is extra risk of trapping moisture and thus rot or mold infections such as crawl spaces and cathedral ceilings where roof venting may be absent or minimal we prefer to use closed cell foam insulation products or spray. Minimize penetrations to the ceiling and especially avoid recessed ceiling lights which have been the cause of numerous moisture problems in cathedral ceilings with or without vent channels.

Above the insulation leave a 1 1 2 in. Vent channel separated from the insulation by a foam cardboard or plywood baffle and provide balanced. Yes a cathedral ceiling detail would be very similar but the challenge of many cathedral ceilings is the added structural elements electrical boxes and the desire for wood board ceilings all which start compromising the drywall layer which in your detail is used at the air barrier.