Asbestos cement: the material behind more than just roof sheets
Most searches for asbestos cement land on roofing or wall sheeting, and both are covered elsewhere on this site. This page is about the other shapes the same material was cast into, several of which sit outside the house and rarely come to mind.
"Asbestos cement" names a material, not one product. Most searches for it land on roofing or wall sheeting, and this site covers both in detail elsewhere. This page is about the other shapes the same material was cast and moulded into. Several of them sit outside the house entirely and rarely come up when people think about where asbestos might be.
None of what follows identifies a specific item on a specific property. Only a laboratory analysis does that, and accreditation by NATA is what gives the result something to rely on.
The same mix, poured or extruded instead of pressed flat
Flat and corrugated asbestos cement sheet is made by pressing a mix of asbestos fibre and Portland cement into boards. The same basic mix was also cast in moulds and extruded through dies to make round and profiled items: pipe, guttering and small precast objects. The fibre does the same job in every shape. It gives a brittle cement product tensile strength, which is exactly why the material was used so widely before its risks were understood.
Four moulded forms worth knowing about
| Item | Where it turns up | Why it gets missed |
|---|---|---|
| Guttering and downpipes | Moulded spouting and round downpipes on older houses and outbuildings, from before PVC became the standard product. | Painted the same as any gutter, and rarely anyone's first thought when the question is asbestos. |
| Flue and chimney pipes | The flue for an old solid-fuel heater or incinerator, run up through the roof. | Usually hidden in a roof space or a wall cavity, and easy to assume is ordinary steel. |
| Stormwater and drainage pipe | Rigid pipe used for stormwater drainage and some older agricultural drainage runs. | Buried, so nobody looks at it until it is dug up. |
| Garden edging and small precast items | Straight and scalloped edging strips, and the occasional planter trough, sold for suburban gardens for decades. | Treated as a garden material rather than a building one, so it never makes anyone's checklist. |
Painted and buried, most of it looks ordinary
What connects the four is that each one hides in plain sight. A gutter or a downpipe gets repainted along with the rest of the house. A flue pipe sits where nobody looks unless it starts failing. Buried pipe is invisible by definition.
Garden edging looks exactly like the concrete edging sold today, because it was sold for the same job. None of that makes any of them more dangerous while they are undisturbed. It just means they are easy to overlook when someone mentally ticks off "roof done, walls done, floor done" and calls a property clear.
Dating still comes from the material, not the house
Asbestos was phased out of Australian cement products through the 1980s, and manufacturing, importing or using any asbestos product was banned outright from 31 December 2003. A pipe, a gutter or a garden edge installed before that phase-out is worth treating with the same caution as an old roof sheet.
An item installed since then is not in the same position. A renovation or a replaced section can carry a different age from the rest of the property. That is why a single "the house was built in the 1970s" answer settles less than it sounds like it should.
What not to do to any of it
- Do not cut or saw old guttering or downpipe to shorten it or fit a new bracket.
- Do not grind or saw through a flue pipe join to extend or replace a heater flue.
- Do not break up buried pipe with a mattock or a trench digger to reroute it.
- Do not lift, break or mow over old garden edging to relocate or replace it.
How it actually gets confirmed
The same two honest paths apply here as everywhere else on this site. Presume the item contains asbestos if its age 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 decides what any repair, replacement or removal of these items may involve. The rules and the small-quantity allowances for bonded material differ between jurisdictions. So a figure that applies in one state should not be assumed to hold in another.
Frequently asked questions
Is old guttering ever an asbestos product?
Yes, on some older properties. Moulded asbestos cement guttering and downpipes were made from the same material as roof sheeting, before PVC became the standard product.
Can flue pipes contain asbestos?
A flue pipe for an old solid-fuel heater or incinerator can be an asbestos cement product. It is usually hidden in a roof space or wall cavity and easy to assume is ordinary steel.
Is garden edging ever made from asbestos cement?
Yes. Precast asbestos cement edging strips and small garden items were sold for suburban gardens for decades, and look much like the concrete edging sold today.
How do I know if a pipe or a gutter is old enough to be a concern?
Asbestos cement products were phased out through the 1980s and banned outright from 31 December 2003, so the age of the specific item, not the age of the house, is what matters.
Does the asbestos cement sheeting page already cover this?
No. Sheeting is the flat and corrugated board used on roofs and walls. This page covers the moulded and cast forms of the same material, mostly found outside the house.
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.
- Asbestos Safety and Eradication Agency. Asbestos Product Guide: what products contained asbestos and where they were used
- NSW Government. Asbestos in NSW: the NSW Government asbestos portal