Fiberglass Resources Guide

Finally, there is a company that quotes those prepared–to–buy TODAY the TRUE WHOLESALE cost, charges modest fees, and GUARANTEES savings! Ready buyers “MUST” fill out a quote form to receive a quote! After quoted savings, they pay a fee that SAME DAY. For those NOT ready to buy, use online ESTIMATORS.

Buy Fiberglass Insulation Below Industry Rates!

Factory Steel Overstock is the perfect resource to get Fiberglass insulation below market prices. Whether you want R-Value 10 to 38, you can buy below market rates with Factory Steel Overstock.  In addition, you can request multiple facing options (below). You can get a delivered estimate directly online by clicking INSULATION DYI ESTIMATOR.  You can request a custom insulation quote – guaranteed below competitors’ quotes – by clicking the INSULATION QUOTE-ORDER FORM.  In order to guarantee the lowest rates, Factory Steel Overstock exclusively quotes those willing to pay associated fees AFTER (same day) quoted savings.

fiberglass metal building insulation

Most people are familiar with fiberglass insulation.  It is what was in their attic when growing up–though there have been improvements on its facings.

Steel building insulation is basically blankets of woven long-strand fiberglass that are laminated on one side to a vapor-barrier facing.  Facing materials are applied to fiberglass insulation blankets to serve as a vapor retarder as well as a protected cover over the fiberglass. This vinyl-reinforced backing is far more durable than vinyl alone.  

Standard Features

Pdf of More Detailed Information on Air Barrier System

Pdf of More Detailed Information on Rigid Envelope System

Pdf of More Detailed Information on Banded Liner System

  • Factory Steel Overstock prices fiberglass insulation with a stronger WMP-VR-R “PLUS” facing in lieu of the industry-standard VR-R. 
  • 3″ tab runs along the length of both sides of rolled-out insulation for easier handling during install.
  • Double face tape and patch is a standard inclusion on insulation quoted by building measurements. Quotes of a specific square ft or number of rolls, patch and double face tapes are added upon request.
  • Customers can indicate the cut length of their rolls.
  • Standard insulation width: 3′, 4′, 5′, and 6′.


Pdf of More Detailed Information on Specifications

  • ASTM C991-08, Standard Specification for Flexible
    Fibrous Glass Insulation for Metal Buildings; Type II.
  • NAIMA 202-96 (Rev. 2000) Standard for Flexible
    Fiberglass Insulation to be Laminated for Use in
    Metal Buildings.

Understanding R – Value

R-Value is based on measuring the amount of heat loss, or ability to retard the loss of heat flow. Understanding R-value with fiberglass insulation is easy: The R-value is directly related to the fiberglass thickness. The thicker the fiberglass blanket you have, the higher the R-value. Factory Steel Overstock quotes R-Value 10 to 38.

Approximate Thickness             R-Value

2.75″                                                       R – 8

3″                                                            R – 10

3.5″                                                         R – 11

4″                                                            R – 13

6″                                                            R – 19

8″                                                            R – 25

9.5″                                                         R – 30


Simple Installation Procedure for Single Layer Blanket

Pdf of More Detailed Recommendations for installing Fiberglass Insulation

  1. You simply place the insulation roll over the top of the roof purlins and / or wall girts. This is done prior to the exterior metal panels being installed.
  2. The fiberglass rolls are essentially sandwiched between the interior metal and the exterior sheeting.
  3. The vapor barrier (usually white finish) is faced towards the inside of the building, giving the building a clean finished look. We always Re-enforce this facing so that our customers have the most sturdy backing. With a single layer application, you can achieve R-Values up to R-19, but not higher.
  4. The 3” tabs are to be rolled over and stapled. Orders come with double-sided tape for easy adherence to building, and a small supply of patch tape to assist with minor tears if needed

Simple Installation Procedure for Double Layer Insulation System: 

The great thing about fiberglass insulation is you can just add an additional layer and increase your R-value. The highest R-value you can have with a single layer of insulation is R-19 which is 6”.  Your purlin depth determines the thickness of your bottom layer.

  1. Faced fiberglass ( we always include a reinforced faced backing) rolls are installed between the purlins and / or girts, filling the cavity. This cavity is important, for it allows the insulation to maximize its efficiency.
  2. This insulation is secured by banding that is screwed to the underside of the purlins. An additional layer of unfaced insulation is then placed over the top of purlins or girts, creating a double layer high R-Value system.

Why do I need insulation?

An insulation R-value is the measurement of a material’s ability to stop heat and cold transfer.  No matter what a metal building’s usage, insulating it will be of value.  Because of the unique nature of a steel building, it requires a vapor barrier and radiant barrier. 

  • The summer heat (sun’s ray) on a steel surface will create extreme heat temperatures inside the building.
  • In addition, the cold winter temperatures are exaggerated by the metal roof and wall sheeting making it frigid inside.  Warm temperatures coming in contact with cool metal roofs or walls create sweating (condensation). 

Options for Vinyl Vapor Barrier Facings

For most standard uses of your metal building, this is sufficiently strong and adequate for being tear-resistant.  We simply wouldn’t settle for less, nor expect you to pay more than the wholesale pricing we pass on to you!

Things to consider when buying Fiberglass insulation:

Be aware there are insulation systems that are of low quality. The fabric is thin and cheap and companies use plastic nylon strapping in lieu of VR-R+ and traditional metal banding.  Most erectors will complain about this kind of banding twisting up on the screw as they try to attach the strapping. 

In addition, some firms will indicate that they have the option to increase the price based on insulation availability. This means these firms can process the order and then hit the customer with an increase at the last minute before shipping. At that point, the customer is stuck and may have to wait several weeks to get their insulation delivered if they don’t accept the price increase. There are a few steel building outlets doing this same tactic.

With Factory Steel Overstock, there are no surprises. If an apple-to-apple price and feature comparison is made, it will be self-evident the better choice!  Needless to say, without the possibility of a price increase after the initial order!

3 easy steps to buy below market rates.

1. Review 1 or more competitor quotes to confirm Factory Steel Overstock savings.

2. Review Building or Insulation PRICES.

3. If you are ready – to – buy NOW, fill out a quote form below!

Insulation FAQ

Q: What R-Values Do You Offer?

A: We offer Fiberglass Insulation R-Value 10 to 38. 

Q: Can I select the width and the piece length of the insulation?

You can with Fiberglass; not with reflective.  Fiberglass widths are 3’,4’ 5’, and 6’. Most people request a length of 100’ or less; however, Reflective insulation widths and lengths are predetermined.  R -15.3 and 17 are 4’ width and 175’ length (700 sq ft). R-22 is 4’ x 85.3 (341 sq ft)

Q: Which insulation type should I choose?

A: Our customers are equally satisfied with both Reflective insulation and our Fiberglass insulation types. Customers located in the North are more apt to buy our fiberglass blanket materials and customers located in the Mid and Southern tend to purchase our reflective insulation. This may be because of a familiarity with an insulation type; however, the most popular purchase nationally is our High R-Value 22 Reflective Insulation.  If your building has ALREADY been erected, the reflective insulation will be quicker to install because it is lighter and can be cut and maneuvered around rafters easier than fiberglass. 

 Q: Do I need a forklift to unload?

A: No, rolls are generally no more than 3′ diameter and packaged for easy unloading from trucks.

Q: Can I mix the types of insulation you offer?

A: Yes, however, we cannot calculate the exact final R-Value when you mix types. All our customers choose one or the other and don’t mix the insulation.

Q: What is the delivery window?

A: Insulation ONLY orders- Reflective is delivered approximately 7 – 10 days and fiberglass within 4 weeks.

Q: Do I need to be present to sign off for delivery?

A: Yes, unless you inform us differently. The shipper will contact you directly to schedule a delivery appointment.

Q. Why Buy Metal Building Insulation From Factory Steel Overstock?

When all the dust settles, it is about price, quality, and service:


Factory Steel Overstock has acquired the expertise and buying leverage to secure the lowest industry insulation prices from two of the largest insulation laminators.  Needless to say, it gladly passes these savings down to the general public.  As a matter of fact, Factory Steel Overstock guarantees a $200 savings below any other insulation quotes for reflective and fiberglass insulation. Average savings is a net 10%.


Factory Steel Overstock makes sure it only offers insulation that meets or exceeds industry standards and has certifications for its ratings 


Rest assured, you will receive a detailed invoice before payment that details sq. ft., piece sizes, description of insulation as well as  R-value. After order, you will receive a call directly from the insulation company or shipper confirming the insulation delivery date.

The best reflection of a company is what previous customers say; therefore feel free to read our BBB report or posted testimonials. Whether you want insulation for your metal building, pole barn, or house – there is no better source than Factory Steel Overstock! 

Q. How can Factory Steel Overstock offer the lowest price insulation and still deliver the high-quality material?

A: In order to offer the highest quality insulation materials as well as offer the lowest industry rates,  Factory Steel Overstock reduces operational cost. It does this by quoting only those willing to buy their insulation after a quoted savings. Payment is made on the same day as quoted savings. Please keep in mind, Factory Steel Overstock will not compromise its selling requirements for a sale. If you are willing to pay for your insulation on the same day as quoted savings, then it is best that you consider a different company!