What Is Asbestos? Why It’s Dangerous for Your Health, Home, and Property

14 October 2026

Everyone knows asbestos is bad, but what exactly is it? It’s common knowledge that it might be found in old buildings. Yet unless you work in the industry, you likely know little beyond the basics.

That gap matters. Around 220 New Zealanders die from asbestos-related disease every year, and WorkSafe says buildings constructed or renovated before 2000 are likely to contain it.

So, what is asbestos, and why is it dangerous? We take a closer look at where it comes from, the health risks of asbestos exposure, and what it means for your property.

What is asbestos?

Asbestos is a group of six naturally occurring minerals. Each consists of tiny fibres and comes from metamorphic rocks. The name asbestos, meaning ‘unquenchable’ in Greek, is a nod to how well it resists fire.

These fibres are incredibly strong and durable. They resist chemicals, wear, heat, and fire, which is why they were widely used in everything from oven mitts to ceiling materials throughout the mid-1900s.

There are six types of asbestos in all, split into two families: serpentine and amphibole. The three most often found in New Zealand buildings are chrysotile (white), amosite (brown), and crocidolite (blue).

How asbestos ended up in New Zealand buildings

Most of New Zealand’s asbestos was imported, mainly from Canada, with small amounts mined near Upper Tākaka. It was used widely from the 1940s to the mid-1980s.

Raw blue and brown asbestos imports were banned in 1984, raw white asbestos in 1999, and all asbestos-containing products in 2016. But existing stock kept being installed, so homes built or renovated up until 2000 can still contain it.

asbestos

Why is asbestos dangerous?

Asbestos is highly dangerous because it is a carcinogen (cancer-causing). This applies to all forms of the mineral, and it’s especially scary because there is no known ‘safe’ level of exposure.

It affects humans because it is a very fine fibre, and when this fibre breaks up and gets into the air, we breathe it in. The fibres lodge in the lungs and the lining around them, and your body can’t break them down.

So why is asbestos dangerous for some people more than it is for others? It comes down to dose. While a single low exposure isn’t considered high-risk, you’re more at risk with each additional exposure.

Friable vs non-friable: why condition matters

Friable asbestos crumbles by hand and releases fibres easily. Pipe lagging and some old insulation fall into this group, and these Class A asbestos products carry the highest risk.

Non-friable asbestos is bonded into materials like cement sheet or vinyl. These Class B asbestos products are low-risk while intact, but cutting, sanding, or water blasting can release fibres.

asbestos

What are the health risks of asbestos exposure?

What are the health risks of asbestos? Breathing in fibres can cause a range of serious illnesses, and symptoms often don’t appear for decades. You might see this called asbestos poisoning, but it usually means one of these conditions:

Condition What It Affects Typical Time to Appear
Asbestosis Scarring of the lung tissue that worsens breathlessness. Usually 10 to 20+ years
Lung cancer Tumours in the lung itself. Smoking greatly increases the risk. Usually 15 to 25 years
Mesothelioma Cancer of the lining around the lungs (pleura) or abdomen (peritoneum). Almost always linked to asbestos. Usually 20 to 50 years
Pleural plaques and thickening Plaques are usually harmless patches on the lung that show past exposure. Wider thickening can restrict breathing. Usually 20+ years

Tradies, demolition crews, and DIY renovators face the highest risk. Their families can also be exposed through dust carried home on work clothes.

The health risk of asbestos in houses: where it hides in Kiwi homes

If your home was built or renovated before 2000, there’s a real chance it contains asbestos. The good news is that the risk stays low as long as the materials are intact. Common places we find asbestos include:

  • Fibre-cement roofing, cladding, and soffits
  • Textured or stippled ceilings
  • Vinyl floor tiles and sheet vinyl backing
  • Bathroom and laundry linings
  • Pipe lagging, older switchboards, and fuses
  • Fibre-cement fences, sheds, and garages

Unfortunately, once it’s mixed into household products, it doesn’t have a distinct look, so you’re unlikely to spot it. Our guide on what asbestos looks like covers the common clues, but only lab testing can confirm it.

Asbestos risk in property renovations, house sales, and workplaces

Asbestos risk in property goes beyond health. It can affect renovation budgets and even a sale.

Renovating or doing DIY work

If you know you have it on your property and want to renovate, you will need an expert to remove it safely so you don’t endanger construction workers or those living on the property. WorkSafe has also prosecuted contractors for water blasting asbestos roofs and cladding.

Earthquake and storm damage

Wellington’s wind and earthquakes can crack old roofing and cladding, turning low-risk material into a hazard. Get damaged material tested before repairs start.

Buying or selling

If you’re buying a pre-2000s home, knowing whether it contains asbestos helps you budget for renovations and avoid surprises after settlement. If you’re selling, testing suspect materials before listing lets you answer buyer questions confidently.

Businesses and workplaces

Businesses in control of a workplace have legal duties under the Health and Safety at Work (Asbestos) Regulations 2016 to protect workers and visitors from asbestos exposure.

What to do if you think you have asbestos

Expert asbestos testing is required to determine whether it is present, and we strongly recommend against DIY testing due to the inherent danger. Our team collects samples safely and sends them to an accredited laboratory.

If the fibres remain intact in materials such as ceiling tiles, the risk is generally low, as long as they’re in good condition and unlikely to deteriorate.

If it needs to come out, the work must be done by a WorkSafe-licensed removalist. Our asbestos removal services cover everything from set-up through to disposal.

Frequently Asked Questions

Is asbestos dangerous if it’s left alone?

Usually not. Undisturbed asbestos in good condition is low risk. The main asbestos risks in houses come from damage, deterioration, or disturbance.

Is asbestos banned in New Zealand?

Importing asbestos products has been banned since 2016. Asbestos already in buildings isn’t illegal, but any work on it must be done safely.

Can one exposure to asbestos make you sick?

It’s unlikely, but we can’t rule it out because no safe level is known. Risk builds with every exposure, so the goal is to avoid breathing in fibres altogether.

What should I do if I’ve accidentally disturbed asbestos?

Stop work and keep people and pets out of the area. Don’t sweep or use a household vacuum, as this spreads fibres. Next, call a licensed professional to clean up.

Can I remove asbestos from my own home?

The asbestos regulations don’t cover homeowners doing DIY in their own home, but WorkSafe strongly advises against it. Friable asbestos should always be removed by a licensed removalist.

Professional asbestos removal across the Wellington region

With so much older housing stock around the country, asbestos is a prevalent and serious problem for Kiwis.

If any of these asbestos risk factors apply to your place, or you’re still asking what asbestos is and why it’s dangerous, we can test suspect materials and talk you through your options.

PRO Environmental Services offers safe and efficient asbestos removal across the Wellington region, Hutt Valley, Kāpiti, and the Wairarapa. We handle testing, asbestos removal, demolition, and clean-up as one team on one quote.

We’re a small, high-performing team. We look after our people first, so they can look after your family and your property. Contact us today to get an asbestos removal quote for your property.

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