Asbestos cement sheet: safe to paint, unsafe to sand

Asbestos cement sheet was used extensively in Australian housing until it was phased out, with a full national ban from 31 December 2003. Anything built before the mid-1980s in Perth is likely to contain it somewhere, and anything before 1990 might.

Where it turns up

• Eaves lining and soffits — extremely common
• Wall cladding on fibro homes
• Bathroom and laundry wall sheeting
• Under-tile and behind-tile sheeting
• Fencing
• Backing to meter boxes
• Roof sheeting on older sheds and carports

Eaves are the one that matters most for painting, because almost every exterior repaint on a pre-1990 house involves them.

The actual risk

Asbestos cement is **bonded** (non-friable) asbestos — fibres locked into a cement matrix. Undisturbed and in sound condition, it is not releasing fibres and it does not present a meaningful risk.

The risk comes entirely from **disturbance**: anything that abrades, cuts, drills, breaks or high-pressure blasts the material releases respirable fibres.

So the rule is simple and absolute:

Painting it is the right thing to do

Coating asbestos cement is actively good practice. A sound coating encapsulates the surface, stops weathering degrading the matrix, and reduces fibre release over the material's life.

The correct method:

1. **Assume it is asbestos** on any pre-1990 sheeting unless you have had it tested. Testing is inexpensive through a NATA-accredited laboratory.
2. **Clean gently.** Low-pressure wash or hand washing with a soft brush and detergent. No high-pressure cleaning — it erodes the surface and releases fibres.
3. **Let it dry.**
4. **Do not prepare mechanically.** No sanding, no wire brushing.
5. **Prime with a sealer** suited to cement sheet.
6. **Two topcoats.**

Where the coating is flaking, wet-scrape only — keep the surface wet throughout, collect debris on plastic sheeting, and dispose of it as asbestos waste.

When painting is not enough

If the sheet is cracked, broken, crumbling, or has been damaged, coating it is not appropriate. Damaged asbestos cement needs assessment and, usually, removal.

Removal in Western Australia is regulated. A licence is required for removing more than 10 square metres of non-friable asbestos, and any amount of friable asbestos must be removed by a licensed friable asbestos removalist. Even under the threshold, there are prescribed methods, and disposal must be at a licensed facility — it cannot go in a skip or a household bin.

This is not a painter's trade. Any painter who offers to "just take the old eaves off while we are here" is doing something they should not.

What to expect from your painter

A painter working on a pre-1990 Perth house should raise asbestos with you before starting. They should:

• Identify the likely ACM on the property
• Explain what they will and will not do to it
• Use wet methods and containment on any flaking coating
• Refuse to sand it, even if asked
• Refer removal to a licensed removalist

If a quote for a 1970s house includes "sand and paint eaves" with no mention of asbestos, that is worth a direct question before anyone starts work.

Owner-occupiers doing it themselves

You are permitted to work on your own home, within the regulations. If you do:

• Wet everything, keep it wet
• Use a P2 respirator, not a dust mask
• Plastic sheeting below to catch debris
• Disposable coveralls
• Never use a household vacuum — only an H-class asbestos vacuum
• Double-bag waste, label it, and take it to a licensed disposal site
• Keep other people and pets away

The Department of Health WA publishes clear guidance on this, and it is worth reading before rather than after.