Guide to Corrugated Asbestos Cement Roof Covering Materials InspectAPedia® -
Maintenance & repair advice for cement asbestos roof materials
Source list for replacement asbestos fiber-cement roof products
Sources for non-asbestos-containing corrugated roofing products
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)
Questions & Answers about identifying & maintaining or removing asbestos cement corrugated roofing
Here is our photo guide and text that can identify the condition of cement asbestos roofing products like asbestos-cement roof shingles. We discuss how to identify corrugated cement asbestos roofing and how to treat this material when found on a building.
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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.
Virtually all of the asbestos cement roof shingle inspection points, installation limitations, and environmental concerns which we discussed at Guide to Cement-asbestos roof shingles also apply to corrugated asbestos-cement roofing products.
OPINION: The lichens growing on cement-asbestos roofing (photo at left), especially this thick corrugated material, is probably less of a wear concern than when that material appears on asphalt shingles or roll roofing.
Do not try to walk on this material without taking the same precautions as if accessing a slate roof: the material is easily damaged by foot traffic.
Cleaning stains, mold algae, lichens from cement-asbestos roofs
Watch out: 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.
Planning demolition of corrugated cement asbestos roofing materials?
The risk of high levels of airborne asbestos from cementious roofing products is probably very low unless the workers are using power equipment like sanders and saws on these substances.
According to NRCA, the National Roofing Contractors' Association, their studies up to February 1992 had not found a single roofing job at which these limits were exceeded, and NRCA reported that in some cases no fiber release was detected. But it appears that the association may have been referring only to asphalt-based roofing materials, not jobs involving the demolition of other ACRM such as cement-asbestos roof shingles (or "asbestos roof tiles" as some consumers refer to them) which might produce different statistics.
See ASBESTOS MATERIAL REGULATIONS and ASBESTOS REGULATION Update that address the handling of asbestos containing building materials, including ACM (asbestos containing materials), PACM (presumed asbestos containing materials), SACM (suspect asbestos containing materials), and ACRM (asbestos containing roofing materials). Also see our articles at ROOFING INSPECTION & REPAIR
Sources of Replacements for Corrugated Asbestos Cement Roofing
Contemporary roofing product manufacturers make reinforced fiber-cement roofing shingles and other roofing products which look like, perform similarly to, and need to be installed similarly to the original corrugated asbestos-cement sheet roofing - but these new products are free of asbestos. (Photo at left: author points to new fiber cement roofing product.)
As we explained in our discussion of cement asbestos shingles, the replacements for corrugated asbestos cement roofing products are reinforced with a variety of fibers including fiberglass.
Other replacements for asbestos-cement roofing use both different fibers and a different aggregate (perlite) to replace the asbestos. Some of the substitute products have been in use for more than 30 years (2008).
Sources of modern fiber cement corrugated roofing (non-asbestos):
For maintenance or replacement of asbestos-cement roofing products contact Supradur Manufacturing Corporation, PO Box 908, Rye NY 10580 800-223-1948, or from within New York State, call 914-967-8230. Ask about their Supradur(R) mineral fiber shingles.
Also seeCORRUGATED ROOFING where we list other corrugated roofing products that do not contain asbestos.
For handling and disposal guidance concerning old roofing material contact the US EPA, your state Department of Environmental Protection/Conservation, or your local building and health departments.
Questions & Answers about identifying & maintaining or removing asbestos cement corrugated roofing
Question: What should I do about corrugated fiber cement roofing on my home - is it asbestos? Is it dangerous?
I just bought my hose...it was inspected...a friend saw my roof, photos [above and below] and says it is asbestos...Can you tell by looking at a photograph if this is an asbestos-cement roof ?
How do I determine if this corrugated roofing is asbestos cement?
Do I need to remove it?
Is corrugated asbestos cement roofing a problem as it is? - S.S.
Reply: It depends ...
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem or that can more accurately estimate the age and thus the chances that your corrugated roof is an asbestos-containing product.
That said, here are some things to consider:
If you know that the material is quite old, say from the 1970's or older, it may be a cement-asbestos product
Because there are fiber cement roofing products that replaced asbestos-fiber-cement roofing products that were subsequently made when asbestos use stopped, and because those newer roofing products look so much like the older asbestos-containing product, without a marking stamped into the roofing material that gives an age, product number or date, or without a lab test on a material sample, and without an idea of the age of the material, one cannot can't reliably guess at whether the material contains asbestos or not.
Were is the building located?
How old is the building?
Are there any receipts for roofing installation that show the date, age, materials, or roofing supplier?
Those questions can also help answer your question about asbestos roofing.
What to do with this corrugated fiber cement or asbestos cement roof
Remember that asbestos is not harmful by its presence alone - it's not radioactive. The potential hazard would be from disturbance and fiber release at high enough levels to form a health risk. In any case the roofing material, even if it contains asbestos, is not an "asbestos roof" - it is a cement roof that may or may not include asbestos in its mix. The "cement" means it's not easiliy friable - it should not easily crumble in to dust if mashed between your thumb and forefinger.
If the roof is not leaking nor damaged, and provided that the roofing has not become soft or broken-up, you do not need to remove it
Asbestos cement roofing is more likely to be a possible problem source of asbestos material if the roof is power-washed or mechanically damaged (such as by running a power saw through it) during demolition or replacement.
Watch out: don't let an inspector or contractor walk on the roof - fiber cement roofing material (asbestos or not) is often fragile enough that it could be broken leading to costly damage.
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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
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.
Thanks to reader Tom Sukeforth, Asbestos & Lead Project Manager, Department of Facilities Management, University of Maine
for updating our information on the current permissible exposure limits (PELS) for asbestos fibers, and for the discussion of PACM.
Presumed Asbestos-Containing Material (PACM) vs. Suspect Asbestos-Containing Material, Michael Kindley, CIHWorkplace Hygiene website, via web search 08/03/2010, http://www.workplace-hygiene.com/articles/PACM-v-Susp.html
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: