When blown into attics and wall spaces loose fill fiberglass offers an average r 2 5 thermal value per inch the higher the number the greater the insulating effect.
Standard depth of blown in fiberglass insulation attic.
How deep to put blown in insulation.
In temperate coastal areas such as zone 3 attic insulation of at least r30 up to a maximum of r60 is recommended.
Each bag of fiberglass insulation will cover approximately 65 square feet of attic space to a depth of 10 inches cellulose insulation covers half as much.
Input depth of existing blown in insulation in inches.
First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation.
Attic insulation is a key to saving energy during the heating season.
Inspecting your attic 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.
Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
Ten inches of blown insulation provides an insulating value of approximately r 30 1 inch of fiberglass provides about r 2 7 while 1 inch of cellulose is approximately r 3.
I wanted an r value between 49 and 60 in my attic so i settled upon a desired depth of twenty inches of insulation.
Fibreglass insulation material has no nutritional value for insects and less likely to get attacked by them.
For instance if you have fiberglass insulation in your attic 12 inches deep the insulation has an r value of 30.
Cellulose attic insulation read more.
To ensure an even distribution i cut a dozen dowel rods to match that depth and then spray painted their top halves a bright orange color.
To arrive at r 38 you need at least 15 2 inches of blown in fiberglass insulation requiring you to add 3 2 more inches of insulation if you already have 12.
A poorly insulated attic lets heat escape through the roof wasting energy used to warm.
You d need a thickness of.
Click the button to calculate the approximate r value for this job.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
