Removing asbestos cement sheets from a lean-to is not a straightforward DIY job — in fact, depending on the quantity and condition of the material, it may be legally restricted work in New Zealand that must be carried out by a licensed asbestos removalist. Before you pick up a crowbar, it pays to understand the rules, the risks, and the right process to protect yourself, your family, and your neighbours.
Is It Actually Asbestos Cement?
Asbestos cement (sometimes called fibro or AC sheet) was widely used in New Zealand for roofing, wall cladding, soffits, and lean-to structures from the 1940s through to the mid-1980s. It typically has a flat or corrugated grey appearance. If your lean-to was built before 1990, there is a real chance the sheeting contains asbestos.
Before doing anything else, have the material tested by an accredited laboratory. An asbestos assessor or hygienist can take samples safely and confirm whether asbestos is present and at what concentration. Do not attempt to sample the material yourself without proper training and PPE — disturbing it can release fibres.
Understanding NZ Law on Asbestos Removal
Asbestos removal in New Zealand is regulated under the Health and Safety at Work (Asbestos) Regulations 2016, administered by WorkSafe NZ. The rules distinguish between two classes of licensed removal work:
| Class | What it covers | Who can do it |
|---|---|---|
| Class A licence | Friable asbestos (easily crumbled) and any asbestos removal over 10 m² | Licensed Class A removalist only |
| Class B licence | Non-friable (bonded) asbestos cement up to 10 m² | Licensed Class B removalist only |
| Unlicensed | Non-friable asbestos cement under 10 m² | Homeowner may do this, with strict controls |
Asbestos cement sheets are generally considered non-friable (bonded) when in good condition — meaning the fibres are locked into the cement matrix and are less likely to become airborne if handled carefully. However, if the sheets are weathered, cracked, or broken, they can behave more like friable material and pose a much greater risk.
Important: Even if you are technically permitted to remove less than 10 m² yourself, WorkSafe strongly recommends hiring a licensed professional for any asbestos removal work. Always check the current regulations at WorkSafe NZ before proceeding.
If You Are Permitted to Remove It Yourself (Under 10 m²)
If the area is under 10 m², the sheets are in good (unfractured) condition, and you have confirmed the material is non-friable asbestos cement, here is the accepted safe approach:
Personal Protective Equipment (PPE)
- A P2-rated (or higher) disposable respirator — not a dust mask
- Disposable coveralls (Tyvek-style), gloves, and boot covers
- Safety glasses or goggles
Key Work Practices
- Wet the sheets thoroughly before and during removal using a garden sprayer with water (adding a small amount of PVA glue can help suppress dust). Never dry-cut, grind, or use power tools on asbestos cement.
- Work on a calm, still day to minimise fibre dispersal.
- Remove fixings carefully — use hand tools only. Avoid breaking or snapping sheets.
- Lower sheets gently to the ground; do not drop or throw them.
- Keep bystanders, children, and pets well away from the work area.
- Seal off the area with plastic sheeting if working in an enclosed space.
Disposal
- Double-wrap sheets in heavy-duty polythene sheeting (at least 0.2 mm thick) and seal with tape.
- Label the package clearly: "CAUTION — ASBESTOS WASTE".
- Contact your local council to find an approved asbestos disposal facility. Not all transfer stations accept asbestos waste, and requirements vary by region.
- Never place asbestos waste in your general rubbish or skip bin.
After the Work
- Dispose of all PPE and coveralls as asbestos waste — do not wash and reuse.
- Wipe down tools with damp cloths and seal those cloths as waste too.
- Shower and change clothes immediately after finishing.
Building Consent Considerations
Removing cladding from a lean-to may also trigger building consent requirements depending on what comes next. Replacing the sheets with new cladding could be exempt under Schedule 1 of the Building Act 2004, but this depends on your specific situation. Always confirm with your local council before starting any structural or cladding work. You can find guidance at MBIE Building Performance.
When to Call a Professional
You should always hire a Licensed Building Practitioner and a WorkSafe-licensed asbestos removalist if:
- The total area of asbestos cement sheeting exceeds 10 m²
- The sheets are cracked, crumbling, weathered, or otherwise damaged
- You are unsure whether the material is friable or non-friable
- The lean-to is attached to a rental property (Healthy Homes obligations apply — see Tenancy Services)
- You are not confident working safely with hazardous materials
- The removal involves working at height or in a confined space
Hiring a professional protects your health, ensures legal compliance, and gives you peace of mind. You can find qualified local asbestos removal specialists on tradedirectory.co.nz.
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