How Much Does Attic Insulation Cost?

You want to update the insulation in your attic, but you're wondering how expensive it will be. Which insulation will be the least expensive? Does the area where you insulate impact the price?

South Central Services has insulated hundreds of homes with spray foam. While attics have many different insulation options, we recommend spray foam for the best performance. If spray foam is out of budget, a few other insulations can deliver good results.

By the end of this article, you will understand:

• Which insulations can be installed in your attic
• Where each insulation can be installed upstairs
• How much each of these insulations can cost

Which Insulations Are Available For Attics?

Since attics are above-ground applications, numerous insulation types are available. The following types of insulation are most common in southern Pennsylvania.

1. Batt insulation
2. Blown-in insulation
3. Spray foam insulation

Within these three types of insulation, there are more choices to make. Fiberglass or rockwool batts? Blown-in fiberglass or blown-in cellulose? Open cell spray foam or closed cell spray foam?

This article will compare the price, versatility, and installation requirements of five attic insulations. We'll start with the most budget-friendly insulations and end with the most premium attic insulation available.

Budget Attic Insulation: Fiberglass Batts

Fiberglass batt insulation is one of the least expensive insulations available. Because of its low upfront investment cost, fiberglass batts are popular for new construction homes and retrofit upgrades in existing homes.

How Much Do Fiberglass Batts Cost?

Fiberglass batts cost anywhere from $1 to $2 per square foot.

The cost of fiberglass batts will vary depending on the R-value of batt you choose. Whether or not the batt is faced can also influence price.

Where Can Fiberglass Batts Be Installed In My Attic?

In attic applications, batt insulation could be installed in either the attic floor or the attic ceiling.

Your insulation cost is impacted by where the batts are installed. Since your attic floor has less square footage than the ceiling, batt insulation for the floor is the less costly option. People generally take this route when they don't intend to use their attic as living space.

Can I Install Fiberglass Batts In My Attic Myself?

Another reason fiberglass batts are popular is their DIY capabilities. If you want fiberglass batts for your attic, you could install them yourself or hire a professional. Installing the insulation yourself will save on labor costs.

If you install fiberglass yourself, be sure to wear the proper personal protective equipment (PPE).

Are Fiberglass Batts In My Attic Worth The Cost?

While fiberglass batts are the least expensive option for your attic, they also offer the poorest performance. Although you may save money upfront by purchasing and installing batt insulation yourself, over the lifetime of your insulation, you will face air leakage and high energy costs.

We do not recommend batt insulation for attics because fiberglass batts do not perform well or make homes more comfortable.

Better Budget Attic Insulation: Blown-In Fiberglass.

Blown-in fiberglass is still a budget option. As a fiberglass product, it tends to be inexpensive.

How Much Does Blown-In Fiberglass Cost?

The average cost per square foot of blown-in fiberglass varies depending on the R-value. A higher R-value requires more product, increasing the price per square foot.

At an R-value of R-49, material costs could range between $1.67 and $2.00 per square foot.

In our climate zone, attics should have a minimum of R-49 for their insulation. However, attics can also benefit from insulation with an R-value as high as R-60. If you opt for R-60 for your attic, material costs will likely exceed $2.00 per square foot.

Where Can Blown-In Fiberglass Be Installed In My Attic?

Blown-in fiberglass can be installed on attic floors, but it cannot be installed in attic rafters. If you want a fiberglass product for your rafters, batt insulation would be the insulation of choice.

Can I Install Blown-In Fiberglass In My Attic Myself?

Homeowners often choose blown-in insulation because it can be completed as a DIY. You can rent a blower machine at Lowe's or Home Depot when purchasing loose-fill fiberglass.

If you choose to install blown-in insulation yourself, you must also account for the machine rental cost. Whether the home improvement store charges a deposit or a rental fee, expect to pay an additional $100 to $300 for equipment rental on top of material costs.

Is Blown-In Fiberglass In My Attic Worth The Cost?

We don't recommend fiberglass in the attic. However, if you are determined to install fiberglass due to its lower cost and DIY capabilities, we recommend blown-in fiberglass over fiberglass batts.

Blown-in insulation can fill in nooks and crannies in the attic, unlike batt insulation. It also doesn't risk gaps or sagging. Instead, blown-in settles over time, requiring more insulation to be installed on top. Returning blown-in insulation to its peak performance is much easier than attempting to fix poorly performing batt insulation.

Best Budget Attic Insulation: Blown-In Cellulose.

Another blown-in attic insulation option is blown-in cellulose. When print media was still popular, cellulose insulation was more affordable. Cellulose was once mostly comprised of recycled newspapers and other print media. However, with the rise of digital magazines and newspapers, cellulose is less recycled and more expensive to produce.

How Much Does Blown-In Cellulose Cost?

Costs will vary depending on R-value, but you can expect costs between $1.70 and $2.30 per square foot for blown-in cellulose.

Due to its density, cellulose will outperform fiberglass. You may be able to arrive at your desired R-value with less cellulose product. However, even though you may need to purchase fewer bags of cellulose, it may not be as inexpensive as loose-fill fiberglass.

Where Can Blown-In Cellulose Be Installed In My Attic?

Blown-in products are meant for the attic floor. A thick and uniform layer of cellulose, meeting the necessary R-value, will accomplish your insulation goal.

Another place where blown-in cellulose could be installed is your attic rafters. When correctly installed by a professional contractor, cellulose can be densely packed into rafters with netting. This application can create an encapsulated attic and a fairly airtight seal.

Dense pack cellulose is technically a different application and would be more expensive than blown-in on the attic floor. Between additional material costs and labor costs, dense pack is a pricier choice. Dense pack is also only feasible for some attics due to unique roof constructions.

Can I Install Blown-In Cellulose In My Attic Myself?

Just like blown-in fiberglass, cellulose can be installed as a DIY. You can save on labor costs by installing blown-in cellulose yourself.

However, the same cost concerns about the blower rental machine apply to blown-in cellulose. Installing cellulose yourself, rather than hiring a professional, may incur rental costs between $100 and $300.

You may also need to invest in some PPE, such as gloves, safety glasses, or a mask.

Is Blown-In Cellulose In My Attic Worth The Cost?

Of all the budget options, cellulose is the best choice for attic insulation. It can be installed by a professional or as a DIY. Cellulose is denser than fiberglass, offering better performance than batt or blown-in fiberglass.

Premium Attic Insulation: Closed Cell Spray Foam.

You may opt for a more expensive product if you have the money to spend on your attic insulation. If you invest in something with better performance, you may save money in the long run.

How Much Does Closed Cell Spray Foam Cost?

Our closed cell spray foam insulation rates are per board foot, not per square foot. You can easily find the board feet of your project by multiplying your square footage by the depth of insulation you need.

For attic applications, closed cell should be between 3 and 6 inches deep. For 100 square feet, an attic would have between 300 and 600 board feet.

The cost per board foot for closed cell spray foam ranges between $1.15 and $1.75.

Compared to budget insulations, closed cell is much more expensive. You could insulate 100 square feet with budget insulation for approximately $2.25 per square foot. Using closed cell spray foam, that 100 square feet could cost anywhere between $4.35 and $8.70 per square foot.

Where Can Closed Cell Spray Foam Be Installed In My Attic?

Closed cell spray foam insulation can be used on attic floors or rafters. By insulating the attic floor, closed cell creates an airtight seal and vapor barrier between your unused attic and living space.

If closed cell is installed in the rafters, the insulation is referred to as an encapsulation. An encapsulated attic makes your attic a conditioned space, just like the rest of your home. This type of insulation is recommended for attics with HVAC ductwork running through because it saves the ductwork from the heat load of an overheated attic.

No matter where closed cell spray foam is installed, it prevents excessive heat transfer, which lowers energy bills over the insulation's lifetime.

Can I Install Closed Cell Spray Foam In My Attic Myself?

Spray foam is not a DIY insulation. While you can find DIY spray foam kits for sale, we cannot recommend installing spray foam yourself.

From a cost perspective, installing spray foam on your own will not save you any money. The material costs of DIY spray foam kits are as high as professional spray foam rates, if not higher.

Is Closed Cell Spray Foam In My Attic Worth The Cost?

Closed cell spray foam can be worth the investment cost for your attic. While the initial investment could cost three times more than budget insulation, closed cell offers better performance than any budget insulation.

Closed cell spray foam cannot be disturbed when you visit your attic. As a spray-applied insulation, closed cell is adhered in place and will not settle, sag, or form gaps. Spray foam has an airtight seal, stopping more heat transfer than budget insulations.

If you choose closed cell spray foam, you'll never have to worry about attic insulation again. Spray foam should last for the lifetime of your home.

Less Expensive Premium Attic Insulation: Open Cell Spray Foam.

If you're interested in the benefits of closed cell but feel it's too pricey, your better option is open cell spray foam.

How Much Does Open Cell Spray Foam Cost?

Like closed cell spray foam, open cell rates are given in board feet, not square feet. To calculate the board feet of your attic using an open cell, you'll multiply your square footage by the depth of open cell spray foam needed.

In attics, 7 to 12 inches of open cell spray foam is necessary to meet R-values and building codes. For 100 square feet, the board feet of your attic could be anywhere between 700 and 1,200 board feet.

Open cell spray foam rates are $0.25 to $0.75 per board foot.

Despite open cell spray foam needing more product installed, the lower rates still result in lower costs overall. For example, when insulating that 100 square feet with closed cell, the average cost per square foot was between $4.35 and $8.70. With open cell, the range is $3.50 to $6.00.

Where Can Open Cell Spray Foam Be Installed In My Attic?

Open cell spray foam is an option for the attic floor or the attic rafters. Insulating the floor will be more affordable than insulating the rafters due to the smaller square footage.

However, if you have any HVAC ductwork running through your attic, we recommend encapsulating by spraying the rafters. Making your attic conditioned like the rest of your home will keep excessive heat load off of your HVAC ducts.

Can I Install Open Cell Spray Foam In My Attic Myself?

Neither open cell nor closed cell spray foam should be installed as a DIY. If you want spray foam in your attic, contact a qualified spray foam contractor.

You may pay a few hundred dollars for their professional labor and expertise. However, that is a small price to pay compared to the cost of removing failed DIY spray foam.

Is Open Cell Spray Foam In My Attic Worth The Cost?

Just like with closed cell, open cell spray foam can be worth the investment for your attic. Choosing open cell spray foam means a permanent solution with an airtight seal. Open cell performs better than budget insulation by stopping the heat that transfers through the air.

Open cell spray foam may be the perfect solution for your attic since it is the less costly of the two spray foam insulations but still offers the premium performance your attic needs.

The Bottom Line About How Much Attic Insulation Options Cost

Attics offer the greatest number of insulation options. As above-grade spaces, they can be insulated with batts, blown-in, dense pack, or spray foam.

The least expensive attic insulation will offer the least performance. You may be able to insulate your attic for as little as $1.50 per square foot. However, any insulation you install for such a low price will have problems, such as sagging, gapping, or settling. You may also have to replace or top off that budget insulation a few years down the road.

The more costly attic insulations are significantly more expensive. Compared to budget insulations, you may spend three to four times more on your investment. However, these pricier insulation products deliver better performance and should last as long as your home.

Now that you know how much attic insulations cost, your next step is to:

• Decide if you want to insulate your attic floor or attic ceiling
• Estimate the cost of spray foam for your attic
• Learn how professional contractors insulate an attic with spray foam