Finding out that your roof might contain asbestos is one of those moments that homeowners often describe as more alarming than the underlying situation actually warrants. Asbestos roofing is a known, well-handled material that's been removed from thousands of New Zealand properties over the last few decades. The process is established, the costs are predictable and the outcome is clean. This post walks through what you need to know.
Where asbestos shows up on roofs
Two roofing materials in New Zealand commonly contain asbestos.
Super 6
Super 6 is a corrugated cement sheet roofing material that was widely used in New Zealand from the 1950s through the early 1980s. It's white to grey in colour, sometimes painted, with a distinctive golf-ball dimpled texture on one face. If you have Super 6 roofing, you can assume it contains asbestos until proven otherwise. Visual identification is reliable; testing is generally not required to confirm asbestos in Super 6.
Decramastic tile
Decramastic is a stone-chip coated metal tile roofing product first manufactured in New Zealand in the 1960s. Tiles produced between the late 1960s and mid-1970s often contain asbestos chips in the surface coating. Tiles produced after that point generally don't. The challenge with decramastic is that you cannot tell visually whether a specific tile contains asbestos. Testing is the only way to confirm.
If your home was built or re-roofed during the relevant period and has either of these materials, asbestos is a realistic possibility. If your home was built after 1984, when the import of raw asbestos into New Zealand was prohibited, the risk drops substantially.
Why the testing matters
Asbestos is hazardous when its fibres become airborne. In an intact roofing material that's sitting on your house and not being disturbed, the fibres are bound into the cement or the coating and the risk to occupants is generally low. The risk rises sharply when the material is cut, broken, drilled, sanded, or otherwise disturbed.
This is why the testing matters specifically when you're considering work on the roof. A decramastic roof that's tested clean can be reroofed using normal processes. A decramastic roof that contains asbestos requires a specialist licensed asbestos removal contractor and a different process. The cost difference is meaningful and the planning is different.
The testing process
Testing is straightforward. A small sample of the suspect material is taken safely, sealed and sent to a specialist laboratory for analysis. Roofbuddy uses Focus Analytics at Mount Wellington in Auckland, which is the standard laboratory for asbestos testing in the upper North Island.
The lab analyses the sample and returns a written result confirming whether asbestos is present and, if so, which type. The turnaround is typically a few working days. The total cost ranges from approximately $80 to $250 depending on the number of samples required for a definitive result.
Roofbuddy covers the cost of this testing for clients considering roofing work through the marketplace. The reason is practical: the test result is what determines the right next step and removing the financial barrier to finding out is the simplest way to make sure the right decision gets made.
What happens if the test confirms asbestos
The removal process is well established and runs alongside the new roof installation rather than as a separate project. Here's what to expect.
Specialist contractor
Asbestos removal is carried out by a licensed asbestos removal contractor, not the roofer. WorkSafe operates a specific licensing regime for asbestos work. Roofbuddy maintains relationships with licensed contractors who handle removal in coordination with the roofing teams in our network.
Sequential removal and replacement
The process runs section by section rather than as a full strip-and-recover. The asbestos contractor removes a section of the old roof and packages the material to the regulatory standard for disposal. The roofer immediately follows behind and installs new roofing material on that section. The process repeats across the property. The advantage of this approach is that the building remains weathertight throughout the job rather than being fully exposed.
Disposal
Asbestos waste is sealed, labelled and transported to a licensed disposal facility. This is included in the licensed contractor's scope of work. There are no actions required from the homeowner beyond providing site access.
Air monitoring and clearance
Depending on the scope, air monitoring may be carried out during and after the work to confirm the removal has been completed to standard. Clearance certificates are issued where required. These confirm the property is safe for normal use after the work.
The cost question
Asbestos removal adds cost to a roof replacement, but probably not as much as you'd expect. The exact figure depends on the size of the roof, the type of asbestos material (Super 6 versus decramastic) and access factors, but the asbestos-removal component is typically a meaningful but not dominant fraction of the overall project cost. Roofbuddy's role is to quote the full project including the removal so you can see the total cost upfront rather than discovering it mid-job.
Where homeowners get caught out is when a non-specialist roofer attempts to handle asbestos material informally without the right licensing. This creates legal exposure for everyone involved, including the homeowner and the disposal of the material is invariably mishandled. The right process costs what it costs because it's the right process.
Living with asbestos that isn't being disturbed
If your roof contains asbestos but is otherwise sound and you're not planning to do work on it, you don't necessarily need to act immediately. Intact asbestos roofing in good condition is generally considered low risk to occupants. The recommended approach is awareness and planning rather than emergency removal.
What you should do is know what you have, keep the roof in good condition (no foot traffic that could damage tiles, no drilling or modifications without a specialist) and plan for removal at the point when the roof reaches end of life or when other work creates the opportunity. Adding solar panels, for example, would not typically be appropriate on an asbestos-containing roof; that's the moment to plan removal.
What to do next
If you suspect your roof may contain asbestos and you're considering work on it, the first step is testing. The testing is inexpensive, the result is definitive and the path forward is clear in either direction.
Roofbuddy covers the cost of testing for marketplace clients and coordinates the full process including the licensed removal contractor and the replacement roofing. You don't need to find separate contractors for each step. The job is managed as a single project with a single scope of work and a single team coordinating the moving parts.
If you suspect asbestos in your roof, talk to a Roofbuddy consultant for testing and a full project scope. Free at roofbuddy.co.nz or 0800 119 998.