# How to calculate how much cellulose for a dense-packed wall?

For the life of me I can't figure out how to calculate how much blown in cellulose we will need for the walls. 2X6 2ft on center with 8 ft ceilings. Applying Insulweb and dense packing.

I hear 3.5lbs per cubic feet

If I just knew how much one cavity would take I could get it figured.

How do is this calculated?

Asked by Gabriel Gonzales

Posted Oct 19, 2013 10:16 PM ET

Edited Oct 20, 2013 8:06 AM ET

Posted Oct 19, 2013 10:16 PM ET

Edited Oct 20, 2013 8:06 AM ET

Tags: General questions

## Other Questions in General questions

### Has anyone had experience with the Unico small duct system?

In Mechanicals | Asked by Andrew Bennett | Apr 29, 15

### Does leaving a service cavity on the inside of a double stud wall make sense?

In Energy efficiency and durability | Asked by John Ranson | Aug 27, 15

### Attic Ductwork

In Energy efficiency and durability | Asked by Janice West | Jul 11, 15

### Re-roof and insulation question

In General questions | Asked by Ted Salyer | Aug 26, 15

### Skipping radiant floor heat in passive house.

In PassivHaus | Asked by Jenz Yoder | Aug 25, 15

Gabriel,

To calculate volume, you multiply width by depth by height.

A typical 2x6 stud cavity might measure 14.5 inches by 5.5 inches by 92 inches.

Multiply the three numbers together, and you get 7,337 cubic inches.

Since 1,728 cubic inches equals 1 cubic foot, we divide by 1,728 to get cubic feet, so:

7,337 cubic inches = 4.2 cubic feet

So, to fill a stud cavity of this size, you'll need 4.2 cubic feet of cellulose. If you are installing the cellulose at a density of 3.5 pounds per cubic feet, you multiply the number of cubic feet by 3.5 to determine how many pounds of cellulose you need.

That means that you need 14.7 pounds of cellulose to fill a cavity measuring 4.2 cubic feet.

Posted Oct 20, 2013 6:13 AM ET