How To Achieve R 49 In Attic

References department of energy.

How to achieve r 49 in attic.

Offers exceptional thermal and sound control performance. Evaluate your house s current r value and recommend whether additional r value is needed and appropriate types of insulation. Fortunately attic insulation can be upgraded simply by adding more to achieve the recommended total depth in inches without removing existing insulation. As dana mentioned use a smart vapor retarder.

Click the button to calculate the approximate r value for this job. X 24 in 6 pieces 48 sq. If you truly need r 49 that won t work but if that is just a target r 46 is close. Fill available space with roxul comfortbatts.

2 r 23 batts will just fit inside a 2x12 rafter for r 46. You can achieve better thermal performance in your attic by adding an additional layer of insulation. Achieving greater r values in exterior walls in exterior walls add insulating sheathing to achieve a greater r value in your wall system. Spray foam insulation r values.

Obviously if you don t have 17 inches of attic space then you ll have to use some other kind of insulation. The table opposite suggests r values by zone as indicated in the map of the united states. Then install a sheet membrane for air tightness. It s been a while since i dealt with insulation but i m pretty sure your gc was talking about the standard fiberglass batting the pink stuff when he said that you would need 17 inches of insulation to reach your required r value of 49.

Input depth of existing blown in insulation in inches. Bag meets r 49 attic code requirements with a single batt. It also suggests r values when adding insulation to uninsulated or under insulated attics crawl spaces and walls. For your attic project install r 49 ecotouch insulation.