Proper Insulation For Vaulted Ceiling

Seal all ceiling openings.

Proper insulation for vaulted 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. This density prevents air from carrying damp into the insulation. Check the joists and wall plates for any holes or openings. Straight bays 2x12 24 o c.

Plus with fiberglass batts you must leave ventilated space further diminishing the insulating potential of the cavity. 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. This will protect the room from air infiltration and will also suppress fires. 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.

Have a newly framed vented cathedral ceiling to insulate. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel. The current plan is to use batts of some kind in the bays take care to air seal the interior surface avoid penetrations air seal the vent channel too bays fully sealed double prime the inside surface for vapor resistance. Be sure to seal around any pvc pipes as well.

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. Fiberglass insulation comes in lightweight batts and rolls precut to widths that match standard stud and rafter spacing. You also need to make sure that you are leaving at least 2 inches of breathing space between the insulation and the roof sheathing. Cellulose insulation s higher r value is very important in limited space areas such as a cathedral ceiling cavity.

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. Foil faced batt insulation is often used in cathedral ceilings because it provides the permeability rating often required for use in ceilings without attics. How to insulate a vaulted ceiling installing a vaulted ceiling requires careful consideration of the building codes in your area.

Then you need to determine the amount of material needed for your ceiling. 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. Stand on a ladder and using a caulk gun seal any areas where there is visible wiring or plumbing. Insulating a vaulted ceiling is similar to insulating exterior walls with.

Nail 1 furring along every rafter side against the roof deck.