Stay off it, and keep water-blasters away
Health NZ warns asbestos-cement roofing breaks easily, you could fall through it, and it's slippery when wet. WorkSafe lists fibrolite sheets among the brittle roofs workers shouldn't walk on. Never water-blast, sand, drill or cut it, and don't let anyone else, including a roof cleaner who knocks on the door.
What it is, and where it hides
Resene says asbestos was mixed with cement to make a light, fire-resistant roofing, sold as tiles or, more often, as corrugated Super Six. WorkSafe lists asbestos-cement roof sheeting and ridge capping, spouting, downpipes, gables and eaves among the places it turns up in homes.
It isn't the only roofing that can contain it. Decramastic tiles made before the early 1980s may have it in their coating, and RANZ adds asphalt shingles and bituminous membranes to the list to test before work starts.
How to find out for sure
You can't tell by looking. WorkSafe says the only way to confirm it is a tested sample, and Health NZ suggests talking to a health protection officer at your public health service before one is taken. We'd have a roofer or asbestos contractor arrange it, so nobody breaks a piece off themselves.
Our asbestos checker and is my roof asbestos? help you weigh up the odds first.
Your options
| What it involves | Worth knowing | |
|---|---|---|
| Leave it alone | No cutting, drilling, cleaning or walking on it | Health NZ says undamaged material isn't a risk just by being there |
| Seal, encapsulate or enclose | Coating or covering it | Health NZ lists these options; Resene recommends replacing or sheeting over an asbestos-cement roof |
| Remove and re-roof | Licensed removal, then a new roof | Takes the risk off the property, with removal rules to follow |
The rules for removing it
Removing more than 10 square metres of non-friable asbestos, such as asbestos-cement sheets, needs a Class B or Class A licence, counted across the whole job. WorkSafe says a large roof can't be split into small sections to dodge the limit. Friable (crumbly) asbestos always needs a Class A licence.
A licensed removalist must notify WorkSafe at least 5 days before starting, tell the neighbours, seal the waste and take it to an approved site. Afterwards, an independent person inspects the area and issues a written clearance certificate. Old asbestos sheets can't be re-used.
The regulations don't apply to work you do on your own home, but Health NZ recommends keeping DIY under 10 square metres, and WorkSafe strongly recommends advice first. On a roof, we'd never suggest it.
Checking the removalist, and the quote
WorkSafe keeps public registers of licensed asbestos removalists and assessors. 'Current' means they can do licensed work; 'Suspended', 'Expired' or 'Cancelled' means they can't.
WorkSafe says a written asbestos quote or work plan should cover the work, any testing, how long it'll take, the price, warranties, the safety measures and the disruption to your home. The ceiling space under a weathered roof can hold a lot of dust, Health NZ says, so ask how they'll deal with it.
Replacing the roof afterwards
Under Schedule 1, removing roof cladding from a building of up to 3 storeys doesn't need consent if it leaves the primary structure, specified systems and fire separations alone. The new roof is a separate question, because a different material can need consent; see building consent for a re-roof.
RANZ suggests telling your insurer before a re-roof, and the Insurance Council says house insurance may not cover you during renovations.
What you can safely do
You can
- Find out when the house and any extensions were built
- Tell anyone quoting for roof work that it may be asbestos
- Keep children and pets away from broken pieces, and don't sweep them up dry
Leave to a roofer
- Arranging a sample and lab test
- Any cleaning, at low pressure only
- Removal by a licensed removalist
- The new roof once it's gone
What we'd do with a Super Six roof
If it's in fair shape and not leaking, we'd leave it alone and keep everyone off it while you plan. Once it's weathered, cracking or letting water in, we'd stop spending on it and plan the removal and the new roof as one job, with a licensed removalist and a roofer who has done it before.
Want a roofer to take a look?
Tell us the job and your postcode. We match it with a Find My Roofer certified roofer who specialises in that kind of work, and they call you to quote. Your number goes to them alone.