Insulating Vaulted Ceiling Rigid Foam

Husband wants to do rigid foam boards double and triple layer have a friend who takes used foam boards out of steel commercial buildings we can pick and choose our boards.

Insulating vaulted ceiling rigid foam.

Foam board insulation would be a more economical especially if you are supplying the labor see photo. Closed cell foam ceiling insulation in a vaulted ceiling offers substantial advantages over open cell. About the only time you are likely to add rigid insulation to a ceiling is in a retrofit of a cathedral ceiling. When applied to the.

These should have straightforward framing with no skylights and with direct access to soffit and ridge vents. In most cases however insulation will not help prevent moisture. Vaulted ceilings require venting as well as insulation. Putting an addition on cathedral ceiling pitch is 12 12 with 2 10 rafters.

He wants a trouble free roof assembly but local advice on insulation and air sealing has been hard to find. Insulating a vaulted ceiling is similar to insulating exterior walls with one notable difference. The roof starts with scissor trusses set on 8 foot centers. The rigid foam layers are installed with staggered seams.

Attics and cathedral vaulted ceilings. Foil faced iso board can be cost effective insulation for finished attics and cathedral ceilings. Rigid foam board installation in the case of a cathedral ceiling involves installing three different layers that are each 1 5 inches thick according to the procedure discussed in this article appearing in fine homebuilding. This is best for simple cathedral ceilings that are easy to ventilate.

R value insulation receives a rating. Johns manville aptm foil faced insulation sheathing board is an excellent choice for insulating attics and cathedral vaulted ceilings. A less expensive alternative is the more traditional vented cathedral ceiling insulated with fiberglass cellulose or open cell foam. First closed cell foam has a 60 percent higher r value per inch than open cell 6 3 vs.

The higher r value reduces condensation when moist interior air hits the now less cold ceiling vice versa in summer with humid outside air. Regular ceilings are likely to be under. Spray foam is a very expensive option however. Polyiso provides one of the highest r values per inch of any rigid insulation r 6 at 1 inch.

How to attach rigid insulation to ceilings. Spray foam closed cell is way out of our budget.