Attic Insulation Batts Over Blown

Before choosing blown vs.

Attic insulation batts over blown.

Cellulose insulation has an average thermal value of r 3 7 so you d need just over five inches to equal an r 19 batt. With the paper face down or up. Any existing batt or roll insulation in the attic should have the facing against the attic drywall floor or no facing at all. Input length width and desired r value of the area to be insulated.

I don t want to add more blow in insulation. Attic insulation is accomplished with either fiberglass blankets batt or blown in insulation. For diy attic insulation you ve got two choices. The vapor retarder on top of or between layers of insulation can trap moisture.

Click the button to calculate the depth in inches and pounds of total insulation required for this job. This calculator is to be used as an estimating tool only. I don t know about that but it s a common insulation material that works much better in the blown form than in batts. Can i even do it this way because of the existing blow in insulation as far as moisture getting in between the blow.

Any new batt or roll insulation installed over existing insulation in the attic needs to be without a vapor retarder face. Unfaced batt insulation friction fit between studs in walls with poly vapor barrier over walls and ceilings blown in attics with minimum r 40 insulation attention to detail. Batt insulation is available at home centers and lumberyards. Loose fill or batt the common term for blanket insulation.

A bag of cellulose runs about 11 50 and will cover 36 7 square feet at a. Whether you live in a warm weather state as i do or in a cooler northern climate it s hard to stay comfortable and keep your energy bills in check if you don t have adequate insulation in the attic. How do i lay the batts over the blown in insulation. If properly done this should not cause a condensation problem in the wall cavity unless you are leaking interior air thru gaps etc.

Blown in insulation requires a professional. My attic has very very little existing blown in insulation in between the joists. Fiberglass comes from what i ve heard one major fiberglass insulation manufacturer call a rapidly renewable resource sand. Batt insulation take time to read this column.

The photo above shows an attic insulated with blown cellulose. Once you ve decided which type is best for you examine the material options and prices to home in on the right product. Both can be added to uninsulated attics or layered over existing material. I live in chicago and my house is cold.

To install fiberglass batts over existing insulation lay the batts perpendicular to the joists so they do not compress the insulation below. I bought r 38 faced batts. Blown in insulation is then applied over the batt level to fill any voids and gaps around joists and other structures and to increase the level of insulation to recommended levels.