Attic Insulation Batts Over Blown

For diy attic insulation you ve got two choices.

Attic insulation batts over blown.

Attic insulation is accomplished with either fiberglass blankets batt or blown in insulation. The photo above shows an attic insulated with blown cellulose. 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. If you are upgrading your attic space we blow in insulation on top of your batt to achieve desired insulation values.

For this we use owens corning propink. Blown in insulation requires a professional. A bag of cellulose runs about 11 50 and will cover 36 7 square feet at a. Fiberglass comes from what i ve heard one major fiberglass insulation manufacturer call a rapidly renewable resource sand.

Batt insulation is available at home centers and lumberyards. 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. With the paper face down or up. Both can be added to uninsulated attics or layered over existing material.

Any existing batt or roll insulation in the attic should have the facing against the attic drywall floor or no facing at all. Before choosing blown vs. 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. My attic has very very little existing blown in insulation in between the joists.

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. Input length width and desired r value of the area to be insulated. How do i lay the batts over the blown in insulation. I don t want to add more blow 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. The vapor retarder on top of or between layers of insulation can trap moisture. I bought r 38 faced batts. Loose fill or batt the common term for blanket insulation.

To install fiberglass batts over existing insulation lay the batts perpendicular to the joists so they do not compress the insulation below. Click the button to calculate the depth in inches and pounds of total insulation required for this job. 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.

In the vapor barrier. Batt insulation take time to read this column. Once you ve decided which type is best for you examine the material options and prices to home in on the right product.