Attic Insulation Levels

Measure your attic s square footage.

Attic insulation levels.

Recommended insulation levels for retrofitting existing wood framed buildings. Add the right kind of insulation. Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live. Each bag lists the required depths for a range of r values and the number of bags needed to cover 1 000 square feet at those depths.

The depth varies quite a bit because we have attic trusses and a floor in the attic. When adding additional insulation you do not have to use the same type of insulation that currently exists in your attic. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. The higher the r value the better the thermal performance of the insulation.

Either read the r value printed on the batts of your existing insulation or use a measuring tape ruler to measure the depth of the insulation inches. Add the following insulation levels to your attic floor. For batts or rolls calculate the number based on the width and length of the product you re using. You will want to record your measurement so you can determine how much more insulation you need to achieve the recommended levels.

R value is a measure of insulation s ability to resist heat flow. In most cases the best type of attic insulation will be blown fiberglass or blown cellulose insulation. For uninsulated attics for attics with existing 3 4 inches of insulation for uninsulated basements or crawlspaces. Add insulation to attic.

The levels of attic insulation recommended today by energy star are substantially higher than those used earlier so it s worth checking out what s recommended in your geographic area. Our attic has between 12 inches and 16 inches of cellulose insulation. Cellulose insulation has an r value of approximately 3 to 3 5 per inch. Existing 3 4 inches of insulation.

For loose fill read labels. Looking across your attic if the insulation is level with or below the attic floor joists you probably need to add more insulation. Insulation levels are specified by r value. Where we re lacking a bit is in the attic.

So we have between r36 and r56 in the attic. Inspecting your attic insulation first things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.