Proper Insulation For Vaulted Ceiling

Check the joists and wall plates for any holes or openings.

Proper insulation for vaulted ceiling.

After you ve reduced humidity problems in your home then air sealed the ceiling between the living space and the attic cathedral ceiling then you can insulate. Cellulose insulation s higher r value is very important in limited space areas such as a cathedral ceiling cavity. Be sure to seal around any pvc pipes as well. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel.

Stand on a ladder and using a caulk gun seal any areas where there is visible wiring or plumbing. This will protect the room from air infiltration and will also suppress fires. You also need to make sure that you are leaving at least 2 inches of breathing space between the insulation and the roof sheathing. Have a newly framed vented cathedral ceiling to insulate.

Seal all ceiling openings. Fiberglass insulation comes in lightweight batts and rolls precut to widths that match standard stud and rafter spacing. Straight bays 2x12 24 o c. Honestly if you ve done your prep work properly you can use cellulose spray foam fiberglass recycled denim or horse hair and your home will be relatively well insulated and energy efficient.

Some builders rely on batts with attached kraft paper facing to do that job but tom recommends unfaced batts covered in plastic with all the seams taped shut. Insulating a vaulted ceiling is similar to insulating exterior walls with. Nail 1 furring along every rafter side against the roof deck. In the knee wall area the insulation is in the floor and on the back of the knee wall.

In most climates it needs a vapor barrier. Cut and insert 1 or thicker high r foam insulation sheets r 8 per inch against the furring giving a 1 or greater air path between the insulation and the roof deck under the cathedral ceiling. Like other batt type insulation fiberglass has a predictable r value if not compressed but is difficult to fit around obstacles without leaving gaps. Instead most builders prefer a foam spray insulation either cellulose or urethane which can be placed into the ceiling using a spray can and left to dry.

Then you need to determine the amount of material needed for your ceiling. Foil faced batt insulation is often used in cathedral ceilings because it provides the permeability rating often required for use in ceilings without attics. This density prevents air from carrying damp into the insulation. How should you insulate.

Plus with fiberglass batts you must leave ventilated space further diminishing the insulating potential of the cavity.