Can You Safely Paint or Plaster Over Asbestos Walls?

Are you budgeting for a home improvement project? Perhaps you’re considering giving your residence a fresh coat of paint? Alternatively, maybe there’s a specific wall that’s rough and uneven, in need of a plaster application? However, any building assembled, altered or refurbished at any point between 1940 and the mid-1980s is likely to contain asbestos — a silicate mineral that can release lethal fibres if disturbed. This begs the question: would you be running health risks by painting or plastering over asbestos?

Why Might Your Walls Contain Asbestos?

Historically, asbestos has — largely due to its strength and fire resistance — long been used as a building material. For much of the 20th century, asbestos was often combined with plasterers Wellington and other coatings intended for walls. As you can imagine, though, asbestos became less and less popular for such purposes as news spread about the health risks posed by the material. Today, it is public knowledge that asbestos fibres can easily become lodged in the lungs and cause potentially fatal conditions, e.g. cancer. New Zealand prohibited the importation of raw asbestos (blue or brown) in 1984, followed by a ban on all asbestos-containing products (with limited exceptions) in 2016. If your home was constructed before October 1st, 2016 when the latter ban took effect, what steps should you take?

Recognising the Risk of Painting or Plastering Your Wall

As it is not possible to spot asbestos with just the naked eye, you should arrange for an asbestos surveyor to inspect the wall for signs of asbestos contamination. It would only be safe to paint an asbestos-containing wall if it is in good condition. Also, you must avoid sanding or abrading the wall lest you damage the asbestos. Due to this risk, some walls can be impossible to plaster without giving rise to dangerous asbestos exposure. One possible option with certain other asbestos walls, though, is to coat them with bonding before following up with PVA and then a skim coat of plaster. Alternatively, you can simply give us the task of painting or plastering over the asbestos-contaminated wall (or at least assessing the viability of doing so). Just call 0800 DECOR8 for more details.  

Frequently Asked Questions

1. Can you paint over asbestos walls safely?

Yes, painting over an asbestos wall can be safe when the surface stays intact and in good condition. Avoid any sanding, scraping, or abrasion during prep, as that action can damage the material.

2. Does painting over asbestos release toxic fibres?

Painting does not usually release fibres when the asbestos surface remains solid, clean, and undisturbed. Fibres can release if the wall gets sanded, scraped, drilled, or if the existing coating breaks up during prep work.

3. Can you plaster over asbestos walls?

Plastering over asbestos is sometimes possible, but it depends on the condition and type of asbestos-containing surface. Some walls cannot be plastered safely because the steps needed to prepare them can disturb fibres. 

4. Can plaster contain asbestos?

Yes, older plaster and textured coatings can contain asbestos, especially in homes built or renovated decades ago. Testing provides the only reliable confirmation before any repair, sanding, or skim coating work starts.

5. How can I tell if my walls contain asbestos before painting or plastering?

You cannot confirm asbestos by sight because it often looks like normal plaster, cement sheeting, or textured coating. A lab test from a small, correctly taken sample gives a clear answer before any work begins.

6. What should I do before disturbing an asbestos wall surface?

Arrange an asbestos inspection before any work that could affect the surface. Keep away from sanding or abrasion until the wall material has been checked.