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Asbestos cement sheeting: what the material actually is

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"Asbestos cement sheeting" and "fibre cement sheeting" describe two different eras of the same idea, and the modern one is sold at hardware stores today. Telling them apart on paper matters as much as telling them apart on a roof.

Asbestos cement sheeting is a specific manufactured product, not just a description of old grey sheet. It is a rigid board made by binding asbestos fibre, almost always chrysotile in Australian building sheet, into Portland cement, pressed and cured into flat or corrugated form.

It was one of the most widely used building materials in the country for most of the twentieth century, on roofs, walls, eaves and fences alike. That is exactly why the generic name causes so much confusion today.

This page is about the material itself, not about identifying it on a particular roof: the checks for that, from the ground, are on the roof identification page. Nothing here confirms asbestos in any specific sheet. Only a laboratory analysis does that, and accreditation by NATA is what makes the result dependable.

What went into the sheet

Asbestos cement is typically a mix of roughly ten to fifteen per cent asbestos fibre with Portland cement and a small amount of other fillers, pressed under load and cured. The fibre is what gives the finished board its tensile strength and lets it be made thin, rigid and weather-resistant without steel reinforcement. A genuinely useful set of properties, which is the reason the product succeeded commercially before its health effects were understood and regulated.

Two shapes, one material

FormWhere it was usedWhat it looks like
Corrugated sheetRoofing, carport and shed cladding, sometimes fencing.Long ribbed sheets, wide corrugations, grey and chalky when weathered. Government product guides record this as one of the most common asbestos cement forms.
Flat sheetEaves linings, internal wall and ceiling linings, wet area splashbacks, barge boards and soffits: and, cut into shingles, occasionally roofing.A smooth or lightly textured rigid board, usually four to six millimetres thick, fixed with visible fixings or covered by a timber cover strip.

Both forms are the same underlying material and carry the same regulatory answer. The corrugated form is covered in more detail on the roof identification page; the flat form used on walls and ceilings has its own page.

When it was made, and when it stopped

Manufacturers progressively phased asbestos out of Australian cement sheeting through the 1980s as non-asbestos fibre cement alternatives reached the market. Then manufacturing, importing and using any asbestos product was banned outright from 31 December 2003.

What settles the question for any given sheet is the age of the material, not the age of the house it is fixed to. A house built in the 1950s can carry a modern fibre cement replacement. And a 1990s extension can carry secondhand sheet that predates it.

The product that replaced it looks almost the same

This is where most of the confusion in a search for “asbestos cement sheeting” actually sits. Modern fibre cement sheeting is made the same way, with the asbestos fibre replaced by cellulose and synthetic fibres. Ordinary building suppliers sell it today for the same jobs asbestos cement used to do. Finished, painted and fixed, the two can be genuinely difficult to tell apart by eye, especially on a sheet that has been repainted more than once.

A few things narrow it down, without ever confirming it. One is a manufacturer's stamp or embossed marking on the back or edge of the sheet: post-2003 products carry one and older asbestos sheet generally does not. Another is a renovation or extension record that dates when a section was fixed. For corrugated roofing specifically, the older asbestos cement product had a wider profile with more widely spaced corrugations.

What not to do to check

None of these clues justifies testing the sheet by damaging it:

  • Do not cut, drill, sand or grind a corner to see what the cross-section looks like.
  • Do not scrape or peel paint back to search for a manufacturer's stamp.
  • Do not snap off a piece to compare its weight or feel to a known sample.

Any of these disturbs the material in exactly the way the rules are written to prevent, for a confirmation that a visual check cannot give you anyway.

How it actually gets confirmed

Two honest paths apply, and they are the same two that apply everywhere else on this site. Presume the sheet contains asbestos if its age, location and appearance are consistent with the older product. And leave it undisturbed: which costs nothing while nobody is working on it. Or have a sample taken and analysed by a laboratory, where NATA accreditation is what gives the result something to rely on.

The WHS regulator in your own state or territory sets which one you need, and what any repair, painting or removal of the sheet may involve. The small-quantity allowances for bonded material differ between jurisdictions, so a figure from one state should not be assumed to apply in another.

Frequently asked questions

Is "fibre cement sheeting" the same as asbestos cement sheeting?

No, not today. Fibre cement sheeting is the modern, non-asbestos version of the same idea, sold at ordinary building suppliers since asbestos was phased out through the 1980s and banned outright from 31 December 2003. The two can look very similar once painted and fixed.

What was asbestos cement sheeting made of?

Roughly ten to fifteen per cent asbestos fibre, almost always chrysotile in Australian building sheet, bound into Portland cement and pressed into flat or corrugated form. The fibre gave the finished board its strength without steel reinforcement.

Was asbestos cement only used on roofs?

No. The same material was made as flat sheet for eaves, internal wall and ceiling linings and wet area splashbacks, and as corrugated sheet mainly for roofing, carports, sheds and some fencing. Roofing and flat-sheet uses are covered on separate pages of this site.

How can I tell old asbestos sheet from new fibre cement sheet without damaging it?

A manufacturer's stamp or embossed marking, which post-2003 products generally carry and older asbestos sheet generally does not; renovation records dating when a section was fixed; and, for roofing, a wider, more widely spaced corrugation profile on the older product. None of these confirms it on its own.

Can I break off a small piece to check what it's made of?

No. Breaking, cutting, sanding or scraping any suspect sheet is exactly the disturbance the rules exist to prevent, and it does not give you a confirmation anyway: only laboratory analysis does that.

Sources

What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.

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