Blog

 

Class B Asbestos Decramastic Roof Removal Auckland – What Every Homeowner Must Know Before Re-Roofing

Class B Asbestos Decramastic Roof Removal – The Real Story for Auckland Homeowners

If your Auckland house still has those shiny pressed metal roof tiles from the 1970s or ’80s — often called Decramastic, Metrotile, or Pressed Metal roofs — you could be sitting under asbestos.

These roofs were coated with a bitumen resin that, back in the day, was mixed with asbestos fibres for strength and fire resistance. Once the coating breaks down or is sandblasted, those fibres can go airborne. That’s where Class B asbestos removal comes in — the legal, controlled method to strip and replace these old roofs safely.

What Is Class B Asbestos Removal?

In New Zealand, asbestos removal is split into two types:

  • Class A: Friable asbestos (soft, dusty material that crumbles easily).

  • Class B: Non-friable asbestos (bonded, solid material — like cement sheets or coated metal tiles).

Decramastic roofs fall under Class B, because the asbestos is trapped inside the coating. But once that coating ages, cracks, or flakes off, the fibres can escape — especially if you walk on the roof or water-blast it.

Keyword focus: Class B asbestos removal Auckland, asbestos Decramastic roof removal NZ, asbestos roof safety Auckland

Step-by-Step: How the Pros Remove a Decramastic Roof Safely

1️⃣ Inspection & Testing

A licensed asbestos assessor takes samples from the roof surface and coating.
These are sent to an accredited NZ lab for analysis. You can’t tell by eye — testing is mandatory before any work begins.

Keywords: asbestos testing Auckland, asbestos Decramastic tile identification NZ

2️⃣ Site Planning & Containment

Once confirmed, the contractor writes a Class B Asbestos Removal Control Plan (ARCP):

  • Identifies roof access points and fall-protection setups.

  • Outlines dust control and wet-down procedures.

  • Lists PPE, tools, and emergency contacts.

The area around your house is cordoned off with warning signage. No one enters except trained, authorised staff.

Keywords: asbestos control plan Auckland, WorkSafe asbestos compliance NZ

3️⃣ Controlled Roof Removal

  • The roof is lightly wetted to prevent dust.

  • Tiles are unscrewed one by one, never broken or ground down.

  • No power tools that create dust are used.

  • Each section is double-wrapped in 200-micron plastic and labelled for transport.

Keywords: Decramastic roof removal Auckland, non-friable asbestos removal NZ

4️⃣ Clean-Up & Air Monitoring

After removal, the team vacuums the ceiling cavity and surrounding surfaces with HEPA-filtered vacuums.
Air monitoring is often done voluntarily to confirm fibre levels are safe before clearance.

Keywords: asbestos air monitoring Auckland, asbestos cleanup NZ

5️⃣ Waste Transport & Disposal

All asbestos-containing waste is taken to a licensed hazardous-waste facility, not your local tip.
Every load is manifested and signed off under HSNO and WorkSafe NZ Regulations.

Keywords: asbestos waste disposal Auckland, hazardous waste transport NZ

Why You Should Never DIY a Decramastic Roof Removal

A Decramastic roof might look easy to strip — it’s just metal tiles, right? Wrong.
Walking on it breaks the coating and releases asbestos fibres into the air.
Even worse, high-pressure washing or sanding spreads contamination across your section and neighbours’ yards.

DIY risks include:

  • Inhaling asbestos fibres (which can cause mesothelioma or asbestosis).

  • Contaminating insulation, gutters, and soil.

  • Fines for illegal asbestos work.

  • Insurance refusing to pay out if contamination is found.

Licensed asbestos removalists are trained, insured, and audited by WorkSafe NZ. They use proper containment, negative-air systems, PPE, and waste control.

Keywords: licensed asbestos removal Auckland, asbestos roof professionals NZ, asbestos safety compliance Auckland

Signs Your Roof May Contain Asbestos

  • Pressed metal tiles with a stone-chip or bitumen finish (pre-1990).

  • Brand names such as Decramastic, Metrotile, Roofshield, Tilcor, or HardieTile.

  • Cracking, flaking, or discoloured coating.

  • Installed between the 1970s – late 1980s.

If in doubt, get it tested — fast and affordable, before you start any work.

Keywords: asbestos roof testing Auckland, asbestos tile identification NZ

The Bottom Line for Auckland Homeowners

If your home still has a Decramastic roof, don’t touch it until it’s tested.
If it contains asbestos, it must be removed under Class B controls by a licensed professional.

Hiring a certified asbestos removalist means:
✅ Safe removal and disposal
✅ Full WorkSafe compliance
✅ Protection for your whānau and neighbours
✅ Peace of mind knowing your property is clean and clear

Don’t risk your health or your home — call in the pros and get the job done right.

Make Enquiry