Blown Insulation Calculator: How Much Blown In Insulation Do I Need?

Finding how much blown in insulation you need to buy for your attic can be a daunting task. But here is a simple calculator for that.

Blown Insulation Calculator

To get the volume of blown in insulation needed, enter the length and width of the attic floor (where you put the insulation), and the R-value required. Then this calculator will tell you how many pounds of insulation you need and in what thickness you need to lay it on the attic floor to get the desired R-value.




Desired R-Value

How much blown in insulation do you need? The math

You need 1.3 pounds of blown in insulation per cubic feet of insulating area. The amount of insulation required depends on the length and width of the area to be insulated as well as how thick the insulation needs to be laid to reach the desired R-value.

As you know the value of blown in insulation is 3.25 per inch. So if you want to have an R-value of 32.5, then you need to lay the insulation in 10-inch thickness. This thickness is used in addition to the length and width of the attic to calculate how much blown insulation you need to buy.

blown insulation calculator

How can this calculator help you?

This calculator will come very handy as figuring out the math on how much blown in insulation you need is not always easy. And if you end up with the wrong R-value, you will not be able to enjoy the results you expect. 

Before you use this calculator though, you will need to know the desired R-Value you want to obtain as well as the dimensions of the surface you want to insulate. Once you have this essential data, insert the values of the length and width of your surface in feet and inches, along with the R-value you need and hit the “Calculate” button. 

When you receive the result, you will get the quantity of insulating material that you will need, in pounds as well as the depth of the layer you need, in inches. 

If you are not sure about the R-value that you want for your blown in insulation, make sure you talk to a specialist to obtain the best recommendations for your home. They will consider the type of surface you want to insulate but also the climate you live in. The R-Value is one of the most important things to know in order to obtain the correct values from this calculator that you can use in your home. 

General Info

What is blown in insulation?

The blown in insulation uses materials such as fiberglass, cellulose or others that have a similar density, thickness and texture. The materials used in blown-in insulation should be easy to fit in tight spaces such as between ducts or wires and in corners that might be difficult to access for other types of insulation. 

Where can you use blown in insulation?

Blown in insulation is commonly used in attics but you can use it in any other space of your home as it will be just as efficient. The most common use for blown in insulation is however, attics as it is the most suitable for such a room. When you choose where to use your blown in insulation, you will have to take into account the benefits that this insulation type will bring to your home. 

This insulation will keep the heat inside your home and block the areas that warm air might escape through during winter season. It is efficient during summer as well since it stops heat from entering your home. 

If you choose a blown in insulation of fiberglass or cellulose, it will also soundproof your attic or any other room you choose to insulate like that. It is important to note that fiberglass insulation is fireproof which adds more safety to your home as well. 

Charles John

A novice DIYer who learns about home ventilation. I am a mechanical engineer and have a basic knowledge of HVAC systems but I learn continuously to make myself the best blogger in that space.

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