Q? What is the difference between a Roll of Insulation and Bag of Batts?

I get this question allot. Typically A bag of insulation batts is much larger than a roll of insulation. When comparing prices its important to compare price per square foot. Thsi is because of many differences in the bag sizes.

Different brands offer different square footages per size. For example a bag of Owens corning R 19 23 Kraft is 118.83 square feet. The same size of R 19 23 Kraft in Johns Manville is 138 square feet. And maybe a roll of R 19 23 kraft has only 40 square feet.

So when comparing prices make sure you are comparing apples to apples. We always ask for square footage needed and then depending on what brand we have in stock we can determine the exact bag count needed and then we can give an accurate quote.

Also when quoting insulation always figure out the square footage not the linear footage.

People often call bags bundles. In the industry we call a bundle a bunch of bags tied together. So a bag is usually how we price and give quotes. But these bags are typically bundles together in set of 4 or 5. This allows for easier transportation storage and handling.


How much do Bundles of Insulation Weigh?

Bundles can be heavy. Check this video on how big a bundle of R 38 is.

A bundle of Insulation is tied together with wire so you can move it around and easily get it to your insulation project. But they can be heavy. I would say they can weight up to 40 pounds. A bundle of insulation is not that easy to lift as you can see me in this video trying to move it around.

What are the dimensions of a bundle of Insulation?

I bundle of insulation typically is 4′ x 3′ x 2′. You can typically fit 4 bundles in a bed of pickup up that has an 8 foot bed.

Vapor barriers work by preventing hot air from your home from infiltrating into the wall cavity. Just as condensation forms on the outside of a glass of cold water left out in the warm air, if the cavity is filled with heated air, droplets of condensation can form within the wall cavity as the hot air from your home is cooled by coming in contact with cold exterior wall.

The moisture from this condensation can result in the growth of mold and mildew inside your wall, which can not only result in rot, but it can also create a significant health risk. Vapor barriers are designed to prevent this situation.

In cold climates, the barrier is applied to the interior face of the wall so that condensation does not form within the wall. Some vapor barriers are created by the Kraft paper faced fiberglass insulation batts. If using unfaced fiberglass insulation batts, a vapor barrier can also be created by installing a poly or plastic sheet on the interior face of the wall.

In warm, humid climates, it is more likely that the warm, humid air will be cooled and form condensation when it touches the vapor barrier cooled from the air conditioning inside the house. If this vapor barrier is on the interior of the wall, this moisture will collect inside the wall and lead to rotting of the wood frame. In such a case, the absence of a vapor barrier will allow more air flow, so that any moisture in the wall can evaporate instead of becoming trapped and causing more long term damage.

When the vapor barrier is applied to the exterior face of the wall, these potential problems essentially flip. Condensation would form inside the wall in a cold climate as the warm air touches the vapor barrier that is cooled by the outside air. Moisture inside a wall can come not only from this process of condensation but also from leaks in the wall or moisture wicked up from a wet foundation by capillary action. In such cases, a vapor barrier may prevent the drying out of the materials in the wall.

Whether or not a vapor barrier is required is determined largely by local and state regulations. The Kraft paper face of insulation batts is a few inches wider than the insulation itself, allowing it to be unfurled and stapled to the studs on either side of the cavity to keep it in place, though a properly sized batt of insulation will hold itself in place with just friction. The paper Kraft face of a fiberglass insulation batt is flammable, so it’s important that it never be left exposed, and is instead covered by some sort of finishing material, such as drywall.

The type of insulation you need depends on what you’re trying to insulate. If you want to add insulation to an existing wall with minimal damage to the existing sheetrock, you’ll need to blow in either loose blow in insulation, like fiberglass or cellulose, or expanding foam insulation. If the studs of your wall are temporarily exposed, you can install much cheaper fiberglass batts. If the studs are going to remain exposed, such as in an attic or crawlspace, you can use a thicker batt with a high R value.

When using insulation batts, it’s also important to check the space between the studs of the area you are insulating. 16 inches on center is the standard in most cases, but studs could be spaced out 24 inches on center in ceiling rafters, garages, or sheds. You’ll want to make sure you’re buying batts of the appropriate width to avoid cutting or leaving empty space.

Another factor to consider is a vapor barrier is required, in which case you’ll need insulation batts faced with Kraft paper, or not, in which case you can use unfaced insulation batts. Whether or not you need the vapor barrier is determined largely by state and local building codes, so make sure to check those before beginning your project.

The R value of insulation that is recommended also varies depending on your location. The Department of Energy has created this map to suggest different R value insulations based on regional climate zones in order to maximize energy efficiency.

R-Zone Values

When insulating a wall with 2 x 4 studs, you can use insulation batts of R 11 or R 13. A wall with 2 x 6 studs can hold batts of R 21. For open stud locations, like ceilings or crawl spaces, you can use insulation of R 30, R 38, or even R 49.

While faced insulation batts are designed so that the paper face can be stapled to the studs, properly sized insulation batts, both faced and unfaced, can be held in place with just friction fit. When installing insulation batts overhead, such as in the case of installing a subfloor, you may want to use batt supports that hold the batts in place without staples.

The price of insulation is constantly changing because, as a building material, its price is determined by supply and demand. When demand for the product is high, the price increases, and when demand for the product is low, the price drops. In May of 2019, for example, the demand for fiberglass blow-in insulation was very high. Contractors were buying it faster than factories could produce it, which resulted in fiberglass blow-in insulation being much more expensive than it was only months before.

For the past 2 years, the construction market has been very strong. The high amount of construction projects has created a high demand for building materials, including insulation of all types, and as a result, prices have increased every quarter. Every 3 to 6 months, the price of insulation has increased, and the next rise in price is expected in June of 2020.

That being said, when comparing different types of insulation when planning a construction project, certain trends usually hold true. • Fiberglass insulation is typically the most economical. Fiberglass batts come either faced or unfaced, depending on if you need a vapor barrier. • Faces batts cost a little more, but the difference is usually pretty slight. • Rockwool and mineral wool insulation tend to be a little more expensive. • Having a professional blow in insulation is significantly more expensive, but the cost is mostly labor, so you can sometimes save money by renting the equipment to blow it in yourself.

Noting that the price of insulation can vary greatly based on demand, below is a comparison of the price of various types of insulation (as of December of 2019). The price depends not only on the style but also the R rating (the measure of how well it prevents the transfer of heat) of the insulation.


When Insulating Exposed Stud Wall

Fiberglass batts: (Estimates) 

  • R 11: $0.21 per square foot
  • R 15: $0.48 per square foot
  • R 19: $0.35 per square foot
  • R 30: $0.56 per square foot
  • R 38: $0.66 per square foot

Non-fiberglass batts:

  • mineral wool: $0.40 per square foot
  • cotton: $0.60 per square foot
  • wool: $2.75 per square foot

Because there is limited space within the wall cavity, and compressing insulation decreases its effectiveness, the only way to increase the insulating property of the wall is to install insulation with a higher R value, which tends to be more expensive.

Expanding Foam:

  • cementitious foam: $1:40 to $2 per square foot of a 2 by 4 wall

When Insulating A Closed Wall

Loose fill blow-in:

  • cellulose: $0.83 per square foot
  • fiberglass: $0.91 per square foot
  • mineral wool: $1.02 per square foot
  • wool fiber: $5.44 per square foot

Expanding foam:

  • open cell: $1.50 to $2.25 per square foot
  • closed cell: $3.50 to $5.25 per square foot

When buying insulation, it’s best to buy in bulk from a local distributor. If you’re buying more than 15 bags, you may be able to get a reduced contractor price. If buying individual bags from a big box store, on the other hand, you will certainly end up paying the maximum retail price allowed.

A material’s R value is a measure of how well the material resists the transfer of heat. The higher the R value, the better the material is at insulating. R value is a term used in reference to building materials that, in other contexts, may be referred to as the material’s thermal resistance. When using the metric system (SI), it may be referred to as the RSI value.

R values can be calculated for not only a given material… (such as polyethylene foam) but also for an assembly of materials (such as a window or a wall). Knowing the R value of an assembled product is often more helpful than trying to calculate how the different component materials, each with their own R values, will interact.

When dealing with individual materials, R value is often expressed in terms of R value per unit of length (i.e., per inch or meter of material). R values are additive per layer of materials, so doubling the thickness of the material will double the R value. This comes into play in construction situations, such as insulating walls. Most walls are built with either 2 x 4 or 2 x 6 studs, leaving only 3.5 or 5.5 inches, respectively, between the drywall. For maximum insulation, you want to fill that cavity with a material with the highest R value.
Attic insulation R Value
A common mistake, however, is to stuff too much insulation into the wall. While it is typically true that increasing the number of layers of a material increases the overall R value, compressing insulation actually decreases its R value. Insulation is designed to have a lot of air pockets because it is the presence of these pockets of air that slows the passing of heat. By compressing the insulation, the amount of air pockets is reduced, allowing the heat to transfer through the material faster, reducing its R value.

For walls with 2 x 4 studs, you can usually use a fiberglass insulation batt with an R value of 13 or 15. If the wall has 2 x 6 studs, you can use a batt with an R value of 19 or 21. In areas that are not fully enclosed, like rafters and crawl spaces, you can use thicker batts with higher R values because there isn’t the risk of compressing the insulation and reducing its R value.

Heat is transferred via three methods, conduction, convection, and radiation, so there are three methods of increasing a material’s R value. Porous insulations trap air, preventing the natural convection that occurs because of air density with temperature.

Highly reflective (low emissivity) materials aluminum foil are often used on exterior surfaces in order to reduce heat radiation. When possible, such as within special closed-pore foam insulations, air can be replaced with argon gas in order to reduce the material’s heat conductivity because argon has a lower thermal conductivity than air.

Placing an order is pretty easy. You can chat with us using our live chat button, you can text us the order, you can email the order or you can call us. Our experts will help you make sure you get the proper quantity and type of insulation.


If you are going to will call then we just need NAME AND EMAIL

We will then send you a confirmation of your order for approval and collect payment. Payment can be made online via our online invoicing system where you can input your credit card or debit card. Or you can call us and we can process payment over the phone.

After payment is received we will schedule the delivery and let you know when your oder will arrive. We try and give you you ETA the day before around 3 pm.

For those who plan on making multiple orders we can create an account for you and we can offer orders on terms? To become a member just contact us and we can set you up!

At the moment (as of 2018)  we only carry Johns Manville and Rockwool. However we are expanding and will soon be carrying Owens Corning and also Certainteed.

Payment is quite easy. We create an invoice that we email to you. There is big Green PAY NOW  button that will take you to a payment page.

insulation invoice

Just enter your credit card info and thats it. We only take credit card.

After payment is made we can either deliver your insulation or release it for will call.

We only take back unopened bags or bundles. All returns are subject to a 25 % re-stocking fee. Delivery fees may apply if we are picking up your material that is being returned.

Delivery distances vary from warehouse to warehouse based on traffic patterns and also the accessibility. Our trucks are typically 32 foot box trucks and they cant fit on some roads. Please text or call to ask about a delivery. Typically we stay within 120 miles of our warehouse locations.