Wear Indicators in Asbestos Cement Roofing Materials InspectAPedia® -
Indicators of wear and age of cement asbestos roofing materials: shingles, corrugated, sheets.
How to recognize asbestos materials in building roofing materials, roof shingles, roof tiles
Photo guide to asbestos-containing roofing products, asphalt shingles, cement-asbestos shingles
Photographs of asbestos containing roofing materials (ACRM)
Non-asbestos materials sometimes mistaken for asbestos
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Here is our photo guide and text that can identify the condition of cement asbestos roofing products like asbestos-cement roof shingles. Our page top photo shows a cement-asbestos roof that is worn out and leaky.
Asbestos cement roof shingles were in popular use in the U.S. from the 1920's (est) through the 1960's (est) and were sold in the U.S. into the 1970's and according to some sources even in the 1980's.. The mixture of asbestos fibers and portland cement to form a hard material that was was durable and fire resistant is credited to Ludwig Hatschek who, in 1900, came up with the name Eternit associated with a U.S. producer of these products.
The typical life expectancy of an cement asbestos shingle roof was given as 30 years, But we have seen these roofs that were now 50 years old in good condition. Typical roof wear or failure patterns are either failure of the shingle fasteners or broken and falling shingles.
Some wear signs to watch for on cement asbestos roofs include these
Active roof leaks - showing up in the attic or living area
Broken cement asbestos roofing shingles (at the left of my hand in the photo above), possibly leaving exposed openings or nails - roof leaks (patch with sheet metal if necessary). Do not try walking on an asbestos cement shingle roof - you'll almost certainly break shingles at every step. (Page top photo).
Freeze-thaw damage: some modern reinforced fiber cement roof shingles are not intended for use in freezing climates and may lack resistance to frost damage. (That's why we don't like leaving moss on shingles.) If you are buying replacement fiber-cement shingles to repair an asbestos-shingle roof, check with the manufacturer about the suitability of the product for your location.
Missing roofing shingles, probably leaving exposed roof sheathing and leaks Moss growing on the roof: we don't like seeing heavy moss or lichens or even leaves or pine needles on a building roof because these hold moisture which can speed the wearing out process, especially in freezing climates.
Moss or lichens on a roof, especially the moss (lichens are hard to remove) can be reduced using industrial cleaners (like deck cleaner) if the contractor works carefully, or even by light brushing; usually we leave moss or lichens alone on an older roof as we are afraid of causing more damage than good.
Mold and staining on roofs (mildew does not grow on roofs) is a mostly cosmetic concern that can be addressed by light gentle spray cleaning with a mildewcide or deck cleaner; be careful not to cause roof damage by too-aggressive use of a power washer.
You can gradually kill off and prevent future moss or lichens or mold on most roof surfaces by installing aluminum or copper strips along the width of the roof near the ridge. Metal salts washing down the roof seem to kill off moss and lichens and most molds. You can convince yourself of the efficacy of this trick by simply noticing how often a roof surface is clean of moss and lichens below areas of metal flashing that are washed by rain. See ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES and also ALGAE STAINS ON ASPHALT ROOF SHINGLES for details.
Power washed asbestos cement shingles or corrugated roofing: As we discuss at Power Washing Roofs we do not recommend power-washing asbestos-cement nor any other roofing. See Black Stain Removal & Prevention for advice on diagnosing, cleaning, and preventing stains on roofing.
Prior repairs using tar, flashing cement - not a durable remedy, leaks likely
Prior roof leaks showing up in the attic or living area, possibly repaired in a less than durable manner.
Roof-over or re-cover limitations for fiber-cement roofs: NRCA says that some fiber-cement roofing products may not be suitable for a "roof-over" application; some roofing manufacturers permit roof-overs with their shingles, but the placement of any new roofing material on an old surface which is not smooth risks future shingle breakage, damage, and leaks. A "tear off" of the old roof is always a better roofing job (and it about doubles the cost).
Slope limitations: beginning in about 1996 the NRCA recommended a minimum slope of 4 in 12 (33%) for these products; use on a low slope means shorter roof life or leaks.
Underlayment requirements: in snow climates an underlayment is recommended to reduce the chances of ice dam leaks. See ... Prevent Ice Dam Leaks on buildings
Asbestos Cement or Fiber Cement Failure Class Action Lawsuit & Settlements
Cal-Shake® Roofing Class Action Lawsuit - 1986-1995 Roofs
How To Identify Cal-Shake Shakes (Cal-Shake, Cal-Slate, Cal-Clay Roofing)
Cal-Shake Shakes are a fiber cement roofing product made to look like wood shakes. Cal-Shake Inc. also manufactured Cal-Slate and Cal-Clay, both of which are included in this settlement. Cal-Shake Shakes were manufactured as shakes and distributed between 1980 and 1995. Please review the information below to see if you have Cal-Shake Shakes installed on your roof. If you take the steps suggested below and are still having trouble determining whether you have a Cal-Shake Shake Roof, please call 1-866-844-0600. Here is a Cal_Shake Claims Form.
Ask the roofer who installed your roof.
Review any invoices, statements, or warranty information that the roofer provided you when the roof was installed or may have been provided to you at the time of purchase by the previous owners of the home.
Review any home-inspection report you may have received upon purchase of your house, which may contain information on the type of roof installed.
Look for broken shakes to see whether the logo "Cal-Shake" is embossed on the top half of the shake.
You do not have a Cal-Shake Shake Roof if:
The shakes on your roof are made of wood
The cement composite shakes on your roof were manufactured by:
American Cemwood,
NatureGuard,
Terra Shake,
FireFree®,
Hardie Shake,
Monier, Owens Corning
Mira Vista,
Protex.
To be a member of the New Cal-Shake Settlement Class, your Cal-Shake roof must have been manufactured between February 1, 1986 and March 31, 1995. The date of manufacture is not marked on the Shake, but if your roof was installed within this period you are probably a member of the New Cal-Shake Settlement Class. People whose roofs were installed very early in this time period might have Old Cal-Shake roofs.
- Web Search 07/12/2010, original source http://www.calshakeclassaction.com/ProductIDnew.html
Hardi-Shake Roofing Class Action Lawsuit & Settlement
On February 14, 2002, the Court granted final approval of the Settlement.
If you own or owned a home or structure with JHBP Roof Shakes, you may be entitled to file a claim for monetary compensation.
A proposed settlement has been reached in a class action lawsuit concerning roofing products manufactured or distributed by James Hardie Building Products, Inc. ("JHBP") under brand names such as HardiShake and HardiSlate, among others. The settlement establishes a program by which claimants can recover the cost of roof replacement, under the terms of the Settlement Agreement. Please read the Court Ordered Notice and other materials available at this site explaining your rights including how to register to receive a Claim Form.
If you have additional questions, you may call 1-888-780-8579 or email hardieclaims@gardencitygroup.com
- Web Search 07/12/2010, original source http://www.hardieroofingclaims.com/
Questions and Answers About Hardie Shake Shingles
Do HardiShakes Contain Asbestos?
Question: I am trying to find out if the old Hardie Shake shingle contained any asbestos?
Reply: Hardie Shakes, Asbestos? Unlikely - Wood Fiber Based Products are Not Asbestos
Modern HardieShake shingles are a [wood-] fiber cement product produced by mixing sand, wood fibers, and cement, rolled to about 1/4" thick and laminated to resist moisture. HardiShake shingle failures manifest as cracked shingles and on older roofs that we have inspected, softening, flaking, and delaminating.
Asbestos fibres would not be expected to be used in wood fiber based products: for example these wood fiber based cementious shingles were designed specifically in search for a replacement for cement-asbestos shingles. So we would not expect to find asbestos in a wood-fiber shingle product.
You should contact James Hardie Building Products in the U.S. or other countries directly for product details, brochures, and installation information.
Masonite fiberboard Roof Shingles & Siding: Information about Masonite roofing products is at MASONITE WOODRUF FIBERBOARD ROOFING. Contact information is at: Chicago, IL, 312-750-0900 . Cass action settlements involving masonite hardboard, omniboard, woodruff shingles. [Watch out: We found the "official" website www.masoniteclaims.com not useful - basically clicking on its links simply present advertisements - web search 09/28/2010]
Cemwood Roof Shakes: Information about American Cemwood roofing shakes and related products is at AMERICAN CEMWOOD ROOFING. Contact information is at: American Cemwood - imitation wood shakes crack, swell and discolor. The American Cemwood roofing settlement includes Cemwood Shakes, Permatek Shakes, Permatek and Permatek II. Cascade Shake, Trieste Tile, Pacific Slate, Permatek II and Royal Shake. Class action settlement site: www.cemwoodclaims.com or for help identifying Cemwood or Permatek shakes on a roof see http://www.cemwoodclaims.com/identify.html Claims administrator: 1-800-708-3266.
FireFree Plus fiber cement Roof Shakes: Re-Con Building Products roof tiles composed of 2/3 Portland Cement and 1/3 wood cellulose fiber crack, swell and discolor. Cass action settlement site: [Watch out: We found the "official" website www.firefreeclaims.com not useful - basically clicking on its links simply present advertisements - web search 09/28/2010 & 03/01/2011]
Re-Con Building Products, Inc., a subsidiary of Stone Mountain Holdings, Inc., went out of business and into receivership in October, 2007.
Also see Fire Free Plus Roofing, 4850 SW Scholls Ferry Road # 203, Portland, OR 97225-1692, Tel: (205) 879-5420
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Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on Asbestos, Its Industrial Applications, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print).
"Handling Asbestos-Containing roofing material - an update", Carl Good, NRCA Associate Executive Director, Professional Roofing, February 1992, p. 38-43
EPA Guidance for Controlling Asbestos-Containing Materials in buildings, NIAST, National Institute on Abatement Sciences & Technology, [republishing EPA public documents] 1985 ed., Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460
Copy on file as - /hazmat/Asbestos_in_Your_Home_US_EPA.pdf - Asbestos in Your Home - U.S. EPA, Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460
Michael D. Coday, (817) 781-9982, a for-fee ($1000 - $3000) roofing claims consultant, original source http://www.find-a-roofing-contractor.com/Hardishake-Guaranteed-Replacement.html - web search 07/12/2010
James Hardie Building Products, James Hardie CustomerLink™ Service Centre, 10 Colquhoun Street, Rosehill NSW 2142, Tel: 13 1103, Outside Australia 61 2 8837 4709,
Fax: 1 800 818 819. Hardie has operations in Australia, Asia, Canada, Europe, New Zealand, United States, and the Philippines. The company is a significant producer of fiber cement siding and backerboard. Email: info@JamesHardie.com and Website http://www.jameshardie.com/
NRCA Roofing and Waterproofing Manual, 4th Ed., available from the National Roofing Contractors' Association.
"Tips for working with fiber-cement roofing products", Thomas L. Smith, AIA, RRC, Professional Roofing, September 1996
"About Asbestos Cement Roof Shingles", Ann Johnson, at ehow.com, a nice article about the history of this material - November 2008.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Asbestos: How to find and recognize asbestos in buildings - visual inspection methods, list of common asbestos-containing materials
Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
Enviro-Scare: Electric Power Lines, Electromagnetic Fields, Cancer Risk, & "Enviro-Scare" - The Normal Curve Cycle of Public Fear of Environmental Issues
Dust from the World Trade Center collapse following the 9/11/01 attack: the lower floors of this building contained spray-on fire-proofing asbestos materials.
Asbestos Information Links: Asbestos Detection, Testing, Recognition, Hazards, Field Photos, and Information Sources, including
health-related links such as legal services and information about mesothelioma and other cancers.
Asbestos Identification and Testing References
Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed
the basis for current work by asbestos identification laboratories.
Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone
For more information about fiberglass as an indoor air quality concern see:
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