Rock Wool / Mineral Wool Producing Companies

Current & Previous Manufacturers

Acoustimac Mineral Rockwool

Acoustimac, 4420 E. Adamo Dr., Ste. 203-204, Tampa FL 33605 USA, Rockboard® 40/60/80,

Roxul Mineral-rockwool ® 60 Acoustic Insulation, Roxul Comfortboard, fire-resistant mineral wool panels, multi-purpose board insulation & acoustic insulation. Tel: 888-827-1266, Website: https://www.acoustimac.com/

ROXUL AFB® is a lightweight, semi-rigid batt insulation specifically designed for steel stud interior wall and floor applications.
This stone wool-based insulation is made from natural stone and recycled content.

ROXUL AFB® ACOUSTICAL FIRE BATTS [PDF] retrieved 2018/06/08, original source: https://www.pharosproject.net/uploads/ files/sources/583/1375800155.pdf

American Rockwool Mineral Wool Insulation

American Rockwool, Corporate Office 1316 Village Creek Drive, Suite 600 Plano, Texas 75093 USA, Corporate Office 1316 Village Creek Drive, Suite 600 Plano, Texas 75093 USA, Tel: 1 (877) 247-5970, Website: Amerrock.com

[Shown in our photo above] Rockwool Premium Plus™ Insulation is a high quality mineral fiber insulation manufactured in a granular form using sustainable products and recycled materials.

Carney Mineral Wool Insulation

Produced by Conwed Corporation, Mankato, Red Wing, Missouri

Celotex Mineral Wool Blankets

Celotex Rockwool Manufacturing Company - photo above of labeling printed on black kraft paper facing used on Celotex insulating mineral wool blankets courtesy of reader Luke, discussed

at CELOTEX HISTORY & PRODUCTS

Conwed Rockwool

See CARNEY MINERAL WOOL

Eagle Richer Mineral Wool Insulation

Eagle-Richer Corporation, Rockwool Industries Joplin Cameron New Jersey

Forty Eight Insulations Co.

Located in Aurora, Indiana

Gold Bond Rock Wool

Gold Bond Rock Wool Insulation - photo above from a 1970's home in Haddonfield New Jersey. Some Gold Bond products contained asbestos.

Gold Bond was a subsidiary of National Gypsum.

Both Gold Bond and National Gypsum filed for bankruptcy in 1990, establishing an asbestos settlement trust fund of $370 million to handle asbestos claims.

Guardian Industries Rock Wool

Current Contact: Guardian Industries, (A Koch company) Guardian Industries Office - Auburn Hills 2300 Harmon Road, Auburn Hills, MI 48326, US Tel: (248) 340-1800 - Since being acquired by Koch in 2014, Guardian Industries is subsidiary of Koch.

Website excerpt:

Guardian Glass, headquartered in Auburn Hills, Michigan, is one of the world's largest manufacturers of float, coated and fabricated glass products.

Also see this litigation

• Johns-Manville Corp. v. Guardian Industries Corp., 586 F. Supp. 1034 (E.D. Mich. 1983) [Web article at Justia)
  Excerpt
  

  Plaintiff Johns-Manville Corporation, a New York corporation[1] (hereinafter J-M), which is involved through its operating subsidiaries in the development and production of fiberglass insulation, has sued defendant Guardian Industries Corporation,[2] a Delaware corporation, and several former J-M employees[3] who have assisted defendant Guardian with its entry into fiberglass production. J-M alleges that defendant has appropriated both patented and unpatented technology developed by J-M for the commercial production of fiberglass insulation that consists of fibers which are less than 7 microns (M) in diameter.
  

Guardian Insulation Solutions - UK

Current Contact: Guardian Insulation Solutions, Unit 2 Tetron Point, 19 William Nadin Way, Swadlincote. DE11 0BB T: 01827 219 327 E: sales@gisuk.co

Established in 2015, the company produces "high performance insulation products" including fire resistant insulation. Products include Knauf mineral wool insulation. - so also

see KNAUF MINERAL WOOL CO.

Johns Manville Rock Wool

Above and below: photos of JM Ful-Thik Rock Wool Insulation, provided courtesy of home inspector Lawrence Transue.

Johns-Manville Corporation (also a producer of asbestos products)

Knauf Mineral Wool Insulation

Below: Knauf Greenguard formaldehyde-free mineral wool insulation.

Knauf Insulation, Knauf Insulation, One Knauf Drive, Shelbyville, IN 46176, USA, Tel: 317-398-4434 Email: info.us@knaufinsulation.com Sales Tel: 800-825-4434 ext. 8576 Website: http://www.knaufinsulation.us/

ACOUSTICAL SMOOTH BOARD Sound Insulation [PDF] retrieved 2019/01/05, original source: http://www.fabsrv.com/wp-content/uploads/2015/08/knauf-acoustical-smooth-board.pdf
Excerpt:

Knauf Insulation Acoustical Smooth Board is a 6.0 PCF thermal and acoustical insulation product made from inorganic glass fibers preformed into boards with ECOSE® Technology. The board is smooth on one side with precision cut tolerances

ECOBATT THERMAL ACOUSTICAL INSULATION [PDF] - retrieved 2018/06/08, original source: http://www.knaufinsulation.us/sites/us.knaufinsulation.com/files/BI-BT-DS_8-17_0.pdf

GREENGUARD IAQ Certified Insulation [PDF] (2010) retrieved 2019/01/05, original source: https://www.knaufinsulation.us/sites/us.knaufinsulation.com/files/content/featured/2010_09_16_KnaufInsulation_CaseStudy.pdf

Above: Knauf Smooth Board sound insulation batts. The color of this and many fiber insulation products is an artifact of the particular binder chosen by the manufacturer.

L. C. Cassidy and Son Mineral Wool Insulation

L.C. Cassicy & Son, 1030 Holt Rd., Indianapolis, IN USA

Cassidy produced mineral fiber insulation.

• Cassidy, Don, and Ray W. Barkhau. Mineral fiber production method and apparatus (Patent at Google Scholar) U.S. Patent 3,883,334, issued May 13, 1975.
  
  Abstract: Disclosed is a conventional apparatus for directing molten, mineral slag onto a spinner rotating on a horizontal axis with annularly arranged steam jets directed parallel to the rotational axis stripping the slag from the spinner and fiberizing it.
  
  This conventional fiber forming system is utilized with a collecting tube having a conical entry portion which is concentric with and faces the stream of fiberized material projected by the steam jets.
  
  The spacing of the mouth of the entry portion from the point of entry of the slag into the steam jets is such as to minimize entry of shot or unfiberized slag into the collecting tube.
  
  The fiberized material is further refined or stripped of unwanted particles by passing it through an inclined portion of the collecting tube and, sequentially, through two, cyclone-type centrifugal separators before collecting it in a conventional bagging apparatus.

Below is a news article about L.C. Cassidy, appearing in The Indianapolis Star, Indianapolis, Indiana, Mon, Aug 10, 1964

Owens Corning Mineral Wool Insulation

• Owens Corning Sound Attenuation Fire Batts, SOUND ATTENUATION FIRE BATT INSULATION / MINERAL WOOL, [PDF] Owens Corning, retrieved 2018/06/08, original source: http://www2.owenscorning.com/around/sound/commercial_acoustics/soundatt.pdf
  
  Excerpt: Sound Attenuation Fire Batts/Mineral Wool (MW) are made of inorganic fibers derived from basalt, a volcanic rock.
  
  The fibers are bonded and formed into flexible batts. The product is manufactured in thicknesses from 1" to 6", and comes in standard metal frame widths.
• SOUND ATTENUATION BATTS [PDF], Owens Corning, retrieved 2018/06/08, original source: https://www2.owenscorning.com/around/ sound/commercial_acoustics/pdf/ SoundAttenuationBatt.PDF
• Owens Corning Thermafiber FREQUENTLY-ASKED QUESTIONS [PDF] (2017) - retrieved 2023/09/08, original source: thermafiber.ca/wp-content/uploads/2018/05/600022A-Thermafiber-FAQ-Document-ENG.pdf

Premium Brand Rock Wool Insulation

Premium Brand Insulation Group, produced rock wool insulation under the following brands:

Indiana Rock Wool Division, Alexandria Indiana, - shown in our illustration, courtesy of reader Dave, June 2018.

Mineral Wool Insulations Division, Fontana, California

Rock Wool Insulating Division, Pueblo, Colorado - shown below, courtesy of reader Ernie Duncan

Texas Rock Wool Division, Belton, Texas

Comment: Premium Brand Rock Wool made in Pueblo CO

Hey there, thank you for what you do, while investigating asbestos content in materials uncovered while doing a remodel I came across your page, just wanted to pass this along if it helps with identification for people and to possibly correct a typo, under the premium insulation portion of this post I noticed "Pueblo, Indiana" as a corporation location I believe that should probably say Pueblo, Colorado rather than Indiana,

the remodel I'm doing is in Pueblo, CO, and Pueblo is also known for it's Steel plant which is responsible for all of the steel railroad tracks west of the Mississippi,

and would also make sense in terms of Rockwool manufacture as all of the associated resources and facilities for Rockwool would have been and still are available here in abundance since the early 1900's, hope this helps and thanks again for what you do. - Ernie Duncan, 2022/01/11

Moderator reply:

@Ernie Duncan,

Thanks so much, that Kraft facing certainly says that that insulation was produced or labeled as Pueblo Colorado. We'll be sure to keep it with this article.

MOST references to Rockwool production in Pueblo do indeed refer to Pueblo, Colorado, as shown in your photo and noted in your post.

There were mineral wool and rock wool and rockwool manufacturing facilities in multiple locations, and as we found in some EPA document searches, there were referenced Pueblo Illinois as location of a rock wool manufacturing plant too. [Or that original source was in error - we are researching that question further]

Premium Brand Insulation Group, produced rock wool insulation under the following brands:

Indiana Rock Wool Division, Alexandria Indiana, - shown in our illustration, courtesy of reader Dave, June 2018.

Mineral Wool Insulations Division, Fontana, California

Rock Wool Insulating Division, Pueblo, Colorado

Texas Rock Wool Division, Belton, Texas

AND

Separately we had this location:

Rockwool Industries Pueblo Illinois [this might be obsolete or was an error in the original EPA source document]

Information source:

US EPA, Source Category Survey: Mineral Wool Manufacturing Industry [PDF] (1980) https://nepis.epa.gov/ cites

"Mineral wool is widely used as a structural and industrial insulation and in ... Rockwool Industries Fontana Colorado Rockwool Industries Pueblo Illinois ..." [this quote is a product of Google search 2022/01/11]

Determine the Age of Premium Brand Insulation Batts?

Can you help me determine when these Premium Brand battings were produced or direct me to a manufacturer's historical product site? - Stacey 2021/07/25

Moderator reply:

On this page you will want to see our description of the Premium Brand insulation company,

Indiana Rock Wool Division, Alexandria Indiana, -

As you will see, that product was produced over many years, so what you're going to need to look for are some black and letters and numbers stamped on the craft facing.

That will give a production run number.

If you can find those and post a photo that would be helpful.

Rockwool Manufacturing Co. Mineral Wool Insulation

Rock Wool Manufacturing Co., 8160 Spruiell St., Leeds, AL 35097 USA - apparently out of business at this address, as mail to this address was returned to us (InspectApedia.com) in November 2020.

Rockwool Manufacuring Co. Mineral Wool Insulation

Also see ROCKWOOL International Co. information just below.

Also see ROCKWOOL TRADEMARK ISSUES

Above: a contemporary RockWool insulation product - this current product does not contain asbestos and we have not found evidence that Rockwools building insulationg products such as batts contained asbestos.

Rock Wool Manufacuring Co., Leeds, Alabama, founded by Edward Cusick Sr. in 1943, began producting a range of insulating products including loose fill or blown-in building insjulation, pipe insulation, and board insulation.

From 1958 to 1970 Rock Wool Manufacturing used asbestos in its asbestsos-cement products and in some building insulation products up to 1980.

Note: we have NOT found an authoritative source that claims that Rockwool used asbestos in building insulationg. But the company is reporeted to have experimented with combining mineral wool ("rock wool") with asbestos where high heat resistance was needed in a product.

For building owners concerned that Rockwool's pipe insulation may have contained asbestos, it's worth noting that the company did not add pipe wrap insulation to its product line until 1988 (Delta brand) - eight years after it had stopped using asbestos in its products.

The Rockwool products that contained asbestos included

Rockwool AF Cement

Delta Maid High Temperature Insulating Cement

Delta Maid One-Shot Insulating Cement

High Temp Master

As a result of lawsuits around its use of asbestos, the company filed for bankruptcy in 1996 and established an asbestos trust to make payments to claimants. The trust fund closed in 2011.

The RockWool Company reorganized and continued in business in 1999 and today has offices world wide and continues to produce a range of "stone wool" insulating products including Cavityrock insulating board and "Safe'n'Sound" insulating batts as well as a wide range of other mineral wool or stone wool products.

"Rock Wool Manufacturing Company Asbestos Trust Agreement", retrieved 2015/12/06, original source: http://www.resasb.org/Pdf%20Docs/trustagr.pdf
Excerpt:

Rock Wool filed a voluntary petition for relief under Title 11 of Chapter 11 of the United States Code (the "Bankruptcy Code") on November 18, 1996

Rockwool Industries Fontana Colorado

Rockwool Industries Pueblo Illinois

Another RockWool insulation brand is Delta Products - also free of asbestos.

Current Company Contact: (Rockwool North America - the company has offices world wide - see below) - Rockwool, Customer service Tel: 1-855-876-3755 (mail: cs@rockwool.com Technical product inquiries: 1-877-823-9790

ROCKWOOL International A/S Hovedgaden 584, Entrance C 2640 Hedehusene, Denmark The ROCKWOOL Group is a producer of stone wool insulation Website: www.rockwool.com

• Rockwool International Website: http://www.rockwool.com/, is a current manufacturer of mineral wool insulation products, or as the company specifies, stone wool insulation, used for fire insulation, sound insulation, and building insulation.
  
  Rockwool International BROCHURE [PDF] (PDF document on rock wool sustainability), Rockwool International A/S · Hovedgaden 584 · 2640 Hedehusene · Telephone (+45) 46 56 03 00 · Telefax (+45) 46 56 33 11 , products include Rockwool Comfortbatt™ fire and sound proofing insulation,
• ROCKWOOL Building Insulation [PDF] (at Rockwool website], ROCKWOOL CHINA Factory： ROCKWOOL China Hotline: 400 665 0505 No.3 Taihua Street, Yonghe District, Guangzhou Economic And Technological Development Zone, Guangdong Province (511356) Tel：(+86) 20 8298 6668 Fax：(+86) 20 8298 6877
  
  PDF Excerpt: We are the world leading stone wool manufacturer ...

Watch out: the term Rockwool is also a trademark for stone-wool insulation produced by Rockwool International, A/S, a Danish company who in our OPINION hold the confusing view that despite NAIMA and many other associations' ubiquitous use of the phrase "rock wool" for stone or rock-based fibrous insulation, their company should have right to use of that term, as explained in this

confusing ROCKWOOL TRADEMARK INFRINGEMENT LETTER [PDF] undated, but sent to us by email by Morten Krusaa, a trademark student assistant at Rockwool Int'l in November, 2016. The writer appears to believe that "rockwool" and also the phrase "Rock Wool" should "... not be used to describe insulation materials or any other products" - perhaps meaning not even their own products.

Many companies, both current and previous producers of mineral wool in various forms, included products labeled as "Rock-Wool" including

According to Rockwool International¹, headquartered in Denmark, in 2016 there remained just five mineral wool / stone wool producers in North America.

Rockwool is currently produced in the U.S. in Indiana, North Carolina, Texas, and Washington State as well as being produced in other countries.

"Descriptive use of ROCK WOOL at InspectApedia, Fair Use + Research Citations", ROCKWOOL International A/S Hovedgaden 584 DK-2640 Hedehusene Denmark Tel: (+45) 46 56 03 00 Fax: (+45) 46 56 33 11 VAT-number: 54879415 Email: info@rockwool.com Personal correspondence, MK to DF 2016/11/22

U.S. EPA, SOURCE CATEGORY SURVEY: MINERAL WOOL MANUFACTURING INDUSTRY [PDF] U.S. Environmental Protection Agency, Office of Air, Noise, and Radiation, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina 27711 (March 1980)

Gold Bond Rock-Wool Insulation, Johns-Manville's Spintex Insulation labeled by the company as "Long Fiber Rock Wool"

at SPINTEX MINERAL WOOL PROPERTIES - MANSVILLE, and Susquehana Premium Brand Rock Wool Insulation

Roxul Mineral-Rockwool Insulation

Roxul Mineral-rockwool ® 60 Acoustic Insulation, Roxul Comfortboard, fire-resistant mineral wool panels, multi-purpose board insulation & acoustic insulation. Tel: 888-827-1266, Website: https://www.acoustimac.com/

ROXUL AFB® is a lightweight, semi-rigid batt insulation specifically designed for steel stud interior wall and floor applications.
This stone wool-based insulation is made from natural stone and recycled content.

ROXUL AFB® ACOUSTICAL FIRE BATTS [PDF] retrieved 2018/06/08, original source: https://www.pharosproject.net/uploads/ files/sources/583/1375800155.pdf

See Acoustimac

ThermaFiber Mineral Fiber Insulation

ThermaFiber, Thermafiber, Inc., 3711 Mill Street, Wabash, Indiana 46992, Toll Free: 888-834-2371 (U.S. & Canada) ; Phone: 260-563-2111, is a current manufacturer of mineral wool insulation products. http://www.thermafiber.com/ Web search 07/28/2010, quoting:

Thermafiber manufactures and customizes mineral wool insulation for commercial buildings, industrial applications and residential construction. We specialize in high-rise construction - that's why we developed Thermafiber Insolutions™, a systematic approach to help you precisely plan and install insulation on time and on budget.

Product description excerpt:

THERMAFIBER FS-15 and FS-25 provide the best possible combination of fi re containment, sound control, thermal insulation, and energy conservation for external walls and ceilings of low-rise or residential structures.

These products are noncombustible, moisture-resistant, noncorrosive, nondeteriorating, mildew-proof and vermin-proof.

Both products resist temperatures over 2000°F as compared to fi berglass insulation that melts around 1000°F. FS-15 and FS-25 can be installed in both wood-frame and steel-frame structures.
- source: Thermafiber® Exterior Wall Insulation FS-15 & FS-25 product data sheet, 2018/06/08

Thermafiber Update: Owens Corning is ceasing its Thermafiber Insul-fill operations in October 2023 with no plans to restart them.

Thermafiber, Inc. One Owens Corning Parkway Toledo, Ohio, iUSA 43659 888-TFIBER1 [834-2371] www.thermafiber.com

For questions relating to product specification, installation inquiries, and assemblies, code questions, LEED® credit information, and health and safety of product (MSDS) contact:

Direct: (260) 569-0801
Email:  GETTECH@owenscorning.com

Thermafiber INSUL-FILL BLOWN-IN ATTIC INSULATION [PDF] Thermafiber, Inc. (Owens Corning)

Excerpt:
Thermafiber® INSUL-FILL™ Blown-In Attic Mineral Wool Insulation is a premium loose fill product specifi cally designed for blown applications in new and existing structures. It can be used as the primary building insulation or as additional insulation in walls and ceilings of existing structures.

This loosefill product can be used to fill areas between cross bracing, truss bracing, and other uneven spaces that are difficult to insulate with traditional insulation batts. Thermafi ber® INSUL-FILL™ blown-in attic wool products are non-combustible, moisture-resistant, and mildew-resistant

ThermaFiber Insul-Fill from Owens Corning

Owens Corning Thermafiber INSUL-FILL SIDE WALL SPRAY Mineral Wool Insulation [PDF] (2017) data sheet - illustrated above - Thermafiber, Inc.
Excerpt:

Thermafiber® INSUL-FILL™ Side Wall Spray Mineral Wool Insulation is a specifically formulated insulation that can be combined with a separate water/latex adhesive solution at the point of insertion. It is a time and labor saving solution providing easy installation into walls and cavities.

Thermafiber THERMAFIBER® INSUL-FILL® INSULATION ATTIC CARD & MANUFACTURER'S FACT SHEET [PDF] gives R-vaoues at various thicknesses

Thermafiber BATT INSULATION INSTALLATION INSTRUCTIONS [PDF] - retrieved 2023/09/08, original source: cdn.thermafiber.com/wp-content/uploads/2018/03/10022787_Thermafiber_Res_Install_Instructions-Final.pdf

Thermafiber SAFE USE INSTRUCTION SHEET [PDF] (2016) - retrieved 2023/09/08, original source: cdn.thermafiber.com/wp-content/uploads/2013/11/Granulated-Products-Safe-Use-Instruction-Sheet.pdf

Thermafiber: ICC-ES VAR ENVIRONMENTAL REPORT VAR-1025 on Thermafiber Insulation [PDF] (2023) on Owens Corning Mineral Wool Products (Thermafiber) - retrieved 2023/09/08, original source: icc-es.org/wp-content/uploads/report-directory/VAR-1025.pdf

Thermafiber: ABOUT THERMOFIBER [PDF] - retrieved 2023/09;08, original source: https://www.thermafiber.com/about-thermafiber/

U.S. Gypsum Mineral Wool Insulation

U. S. Gypsum Company Birmingham Leeds Birmingham California

U. S. Gypsum Company : Lagro Huntington Wabash Alexandria (closed 9/79) Alexandria Wabash Minnesota

US Mineral Products Mineral Wool Insulation

U.S. Mineral Products Company, United States Mineral Products Company (USMP), produced fire-resistant insulation, filed for bankruptcy in 1996, established an asbestos claims trust fund in 2001.

U. S. Mineral Products, Stanhope