Asbestos cement water tanks: the old roof space tank and what to leave alone
Older houses may still have a cement header tank in the ceiling. Intact and unused, it is usually best left alone. Cutting or breaking it is the mistake.
Yes, some old water tanks are asbestos cement. The Asbestos and Silica Safety and Eradication Agency describes them as tanks once commonly installed as header tanks in the roof space of older houses, made before 1990. If your home predates that, a grey tank in the ceiling is worth a second look.
Where asbestos cement water tanks turn up
The usual spot is the roof space. A header tank there fed the household taps by gravity. Some tanks also sit outside the roof structure, and the agency lists flat roof areas on industrial buildings too. At home, start with the ceiling cavity and the area around it.
You cannot tell the material by eye. A grey, rigid tank could be cement, plastic or metal. Treat it as compatible with containing asbestos until a NATA-accredited laboratory says otherwise.
An unused tank can stay where it is
Many of these tanks are no longer part of the plumbing. Where a house is connected straight to mains water, the old tank can be left in place and unused. That is the agency's own description of the situation. Leaving it alone is often the sensible answer.
Do not climb in and start tidying. The tank sits in a roof space where dust collects and where you may brush against it.
Damage is the thing to watch for
The agency notes that the edges of the tank and its lid can be damaged. It also notes that tanks mounted outside can deteriorate from weathering. A cracked rim or a crumbling edge is a different situation from an intact tank. If you see either, stop and keep people out of the area.
Cement of this kind is a bonded material. The NSW Government portal says asbestos in stable, good condition is low risk, and that breaking it is what changes things.
What you should not do
- Do not cut, drill, break up or lift out a tank you think may be asbestos cement.
- Do not scrub it, sand it or clean it with a pressure washer.
- Do not drag an old tank across the roof space or down a ladder.
- Do not put pieces in a normal bin or skip.
Before a renovation or a plumbing job
Tell your plumber and any builder that the house is older and that there is a tank in the roof. A good trade will stop and ask what it is made of. If a tank has to come out, that is a question for your state regulator first. And our guide to what a homeowner can legally remove shows why the answer differs by state. Check your state regulator for the rules where you live.
Water tanks are not the same as water pipes
Cement pipes in the ground and in walls are a separate topic, covered under asbestos pipes and asbestos in drinking water. The tank is a single bulky object. The pipes are runs you may never see.
Frequently asked questions
Are old water tanks made of asbestos?
Some are. The Asbestos and Silica Safety and Eradication Agency lists asbestos cement water tanks, commonly installed as header tanks in the roof space of older houses and made before 1990. Only a NATA-accredited laboratory can confirm a particular tank.
Can I leave an old asbestos cement tank in the roof?
The agency says a tank connected directly to mains water can be left in place and unused. Keep it undisturbed and tell any tradesperson it is there.
Can I cut up or remove an old water tank myself?
Do not cut, drill or break up a tank that may contain asbestos. Whether you may remove one yourself depends on your state, so check your state regulator first.
How can I tell if a tank is asbestos cement?
You cannot tell by looking. Treat it as compatible with containing asbestos and have a sample analysed at a NATA-accredited laboratory.
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 and Silica Safety and Eradication Agency. Asbestos cement water tanks
- NSW Government asbestos portal. Asbestos in the home