If there’s asbestos present in your home, you’ll want be sure that it’s managed properly or removed. But it can be difficult to know whether you should even suspect that asbestos might be present. How do you know what to look for? While there’s no clear cut way to tell if you’ll find asbestos in a property from the outside, there are a few things you should know that can give you some hints. To understand why these factors can indicate the presence of asbestos, it’s important to first understand some of the history of the mineral’s use in New Zealand construction.


Asbestos use in New Zealand

While asbestos was only officially banned from importation in 2016, its use in construction had declined heavily since its peak in the mid-twentieth century when it was discovered to be hazardous.

But during the time it was used, it was used heavily. The year in which the most asbestos was imported into the country was 1974, according to a report by the Royal Society of New Zealand and the Office of the Prime Minister’s Chief Science Advisor; 12,000 tons that year alone. The total imported to the country over its lifetime is somewhere around 200,000 tons, much of which can still be found in residential homes today.

Read more The History of Asbestos in New Zealand


What houses are most likely to have asbestos?

Taking into account the years that asbestos was used most heavily, we can create three rough time periods:

 1940 - 1980: Most likely to contain asbestos.

 1980 - 1990: Likely to contain asbestos.

 1990 - Present: Unlikely to contain asbestos.

Keep in mind these are rules of thumb rather than supremely accurate diagnostic tools. There really is no way to know for sure whether a house will contain asbestos or not, but one of the biggest clues is the time in which it was built. The only real way to determine whether or not their is asbestos in your property is to get an asbestos test. Older New Zealand homes are the most likely to contain asbestos in some form.

Find out more about common places you may find asbestos with our free downloadable guide

What other clues are there that my home might contain asbestos?

Asbestos had a lot of uses in New Zealand, but chief among them was as an additive in building materials. Because the fibres were flame resistant as well as insulating, their addition to many products like roofing tiles or vinyl flooring made them fire retardant too. While asbestos in its pure fibre form was used for insulation in some places, it was mostly only in commercial buildings, with residential insulation most commonly being fibreglass.


Collectively, the asbestos-added products are known as ‘asbestos-containing materials’ (ACMs). When trying to determine whether asbestos is present in your home, ACMs are the things you’re going to be looking for. And while there are a large number of products that asbestos was added to, there are a few common ones that it’s worth knowing about so you can have them tested if you suspect they’re present on your property.


Corrugated cement sheets


Perhaps the most common use for asbestos was in the creation of corrugated cement sheets. The Royal Commission report, for example, states that the majority of homes built in this country between 1940 and 1960 used tile or asbestos-cement sheet roofing. But they weren’t only used for roofs. These sheets were also used for wall cladding, weatherboarding and fencing.

Harmful effects of the material aside, the reason it was so commonly used was because of its beneficial properties. Asbestos is fireproof, meaning any product it was added to had its flame-resistant properties greatly enhanced. The cement material was easy to mould, meaning corrugated sheets were easy to create, and the material on the whole was cheap and durable.

Read moreAre asbestos roof tiles dangerous? 

Asbestos cement products are often also the most risky to homeowners, because sometimes they’re unaware of what they’re dealing with and proceed to high-pressure water blast their asbestos cement roofs or fences.

The problem with this is that there’s a high risk that the harmful asbestos fibres will escape with the pressure and be breathed in. The danger that asbestos presents is not in its toxicity—when contained within an ACM, asbestos is, for the most part, safe. The trouble comes when the tiny fibres enter people’s lungs and cause a number of conditions, cancer being the most deadly. So it’s best to avoid water blasting materials that look as though they might contain asbestos, like cement roofing tiles or sheets.


Textured walls or ceilings

Another common use of asbestos was in textured or ‘popcorn’ ceilings. While they’ve now gone out of fashion (perhaps due to their reputation for containing asbestos, despite the fact alternative materials can now be used), textured ceilings were once all the rage. They were excellent at hiding an uneven or poorly finished ceiling, so were a popular choice for a cheap and quick solution to getting a home to look right.

But as with other ACMs, they pose a health risk when they’re in poor condition and asbestos fibres have the potential to be released into the air.

Aside from corrugated cement sheets or tiles, textured ceilings are probably the most likely place for asbestos to be found in an older home. That said, a textured ceiling doesn’t necessarily have to contain asbestos—your best bet is to have it tested by a professional to determine what materials are present.


Is the presence of asbestos in a home a reason not to buy it?

As with most questions of this kind, the answer is ‘it depends’.

If the asbestos present is in the form of cement roofing tiles or a popcorn ceiling—and those things are in good condition—it may still be worth purchasing the home, provided the price is right and you’ve taken into account the potential cost involved in needing to remove or encapsulate it. Asbestos in good condition will eventually have to be dealt with as it deteriorates, so it’s a ticking time bomb in terms of cost.

And that’s when you’re talking good condition—ACMs in bad condition will need to be dealt with straight away, with asbestos removal being your safest bet. Again, it can still be worth a purchase if the location of the house is great, it has other redeeming features or the price is exceptionally low, but you need to factor in the cost of dealing with the asbestos into your purchasing decision.


If in doubt, seek professional help

The best practice for dealing with potential asbestos in your home is to talk to an expert. Chemcare are licensed professionals that deal with asbestos on a daily basis. Get in touch today to learn more about how we can develop an asbestos management solution for your home.


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