How Do I Know If Asbestos Is Present in the Downpipes of My House?

By Stan G. in Removal

A roof collects a large amount of water. Gutters and downpipes are your home's first line of defense against leaks.

The immediate connection of downpipes to the permanent stormwater system can significantly reduce the amount of water on-site and decrease site wetness. Modern housing is free from asbestos, but cement bonded asbestos materials were used frequently in domestic rainwater downpipes, gutters, water tanks, and insulation boards, prior to 1980. Asbestos-containing material is not generally considered to be harmful unless it is releasing mineral fibers into the air where they can be breathed or swallowed. Once they are trapped in the body, the fibers can cause adverse health effects.

How to Identify Asbestos Cement Products, Such as Downpipes

Up until the late 1980s, asbestos fibers were added into cement mixtures to increase the strength of the product. Roughly, 10-15% of the cement would contain asbestos fibers.

In order to identify asbestos, try to find any codes or markings on the material, and look for any information that the manufacturer stamped or printed. Some asbestos cement products are branded with the letters ACM as an indicator that they contain asbestos. The absence of a code or label does not mean the material is asbestos-free.

Companies that manufactured asbestos cement downpipes include:

  • P. Green Industries, Inc.
  • Armstrong Contracting and Supply Corporation
  • Capco Pipe Company
  • CertainTeed Corporation
  • Crown Cork and Seal Company, Inc.
  • Eagle-Picher Industries, Inc.
  • Fibreboard Corporation
  • Flintkote Company
  • Forty-Eight Insulation, Inc.
  • GAF/Ruberoid
  • Haveg Pipe Company
  • Johns Manville Corporation
  • Nicolet, Inc.
  • Pittsburgh Corning Corporation
  • U. S. Gypsum Company

How to Determine If Asbestos Downpipe Removal Is the Most Appropriate Action to Take

Asbestos is most hazardous when it is friable. The term "friable" means that asbestos is easily broken and damaged by hand, releasing fibers into the air.

Non-friable - bonded asbestos is where asbestos is mixed with other materials, such as cement. This form of asbestos material is quite safe unless damaged, sawn, drilled, sanded, crushed, or is excessively weathered. If any of these occur, then non-friable hard bonded asbestos products may become friable and release fibers.

Examples of non-friable asbestos-containing materials include asbestos cement products like:

  • corrugated sheeting used in walls
  • ceilings
  • roofs
  • molded items such as downpipes

For more information on how to determine if asbestos is present in your home and where it can be found, read our Asbestos Identification page.

Removing asbestos materials from your home is not always necessary. They might not pose a threat to your health as long as the asbestos-containing materials are in good condition. The risk of exposure will be minimal to nonexistent if asbestos in the home is left undisturbed or left to the professionals to remove or contain.

Removing Asbestos Downpipes the Safe Way

It is highly advisable to consider replacing the asbestos material if you identify damage to your gutters and downpipes. In this case, downpipe removal should be carried out safely and dispose of it as hazardous waste.

When removing the asbestos downpipes from your property, consult the following checklist:

  • place clear warning signs to inform people of asbestos removal work
  • ensure that you are wearing the correct safety respirators and disposable overalls for asbestos removal
  • ensure you have double-layered plastic to stack the removed asbestos guttering and downpipes on
  • remove all the screws and brackets that are holding the asbestos guttering and downpipes in place
  • where asbestos removal takes place on grass or garden all contaminated debris will be disposed

For more information about the safe removal of asbestos-containing materials, we recommend you read our Asbestos Removal page.

Why Should I Test Products in My Home for Asbestos?

It is often impossible to tell whether asbestos is embedded in a material, as the fibers are too small to be observed with the naked eye. Exposure to asbestos is responsible for serious respiratory conditions, so thorough testing is required to ensure your home is asbestos-free.