Can I Chip Out Asbestos Cement Mortar from Old Brick Joints Myself?

No — you should not chip out asbestos cement mortar from old brick joints yourself. In New Zealand, this type of work is tightly regulated under health and safety law, and for very good reason: disturbing asbestos-containing materials (ACM) releases microscopic fibres that can cause serious, life-threatening diseases including mesothelioma, asbestosis, and lung cancer. Even careful chipping creates dangerous dust. This is work for a licensed asbestos removalist.

Why Asbestos Mortar Is So Dangerous

Asbestos was commonly mixed into cement-based products in New Zealand from the 1940s through to the late 1980s. Brick mortar, particularly in commercial and older residential buildings, sometimes contained chrysotile (white) or other asbestos fibres to improve strength and heat resistance. When mortar is friable (crumbly) or is mechanically disturbed — even by careful hand chipping — it can release respirable fibres into the air.

Asbestos fibres are invisible to the naked eye. You cannot tell by looking whether you have inhaled them, and the diseases they cause can take 20–40 years to develop. There is no safe level of exposure.

What NZ Law Says About Asbestos Removal

Under the Health and Safety at Work (Asbestos) Regulations 2016, asbestos removal work is classified into two classes:

Mortar that is being chipped or ground is being actively disturbed and made friable, which almost certainly places this work in the Class A category — the most strictly controlled. Even if the mortar starts out non-friable, the act of chipping it creates dust and broken fragments that release fibres.

Homeowners are not permitted to carry out Class A asbestos removal. This is restricted work under WorkSafe NZ regulations, and doing it yourself could expose you, your family, and your neighbours to serious harm — and potentially significant legal liability.

First Step: Get the Mortar Tested

Before any work begins, you need to know whether the mortar actually contains asbestos. Do not assume either way. Have a IANZ-accredited laboratory test a sample — but even sampling should be done carefully and ideally by a qualified asbestos assessor to avoid unnecessary disturbance. An assessor can take samples safely and provide a written report.

If the test comes back negative, you're free to proceed with normal repointing. If it's positive, you must engage a licensed removalist.

What a Licensed Asbestos Removalist Will Do

A licensed Class A asbestos removalist will:

• Prepare a written asbestos removal control plan before starting
• Set up containment and negative-pressure enclosures to prevent fibre spread
• Use wet methods and hand tools where possible to minimise dust
• Wear appropriate respiratory protective equipment (RPE) and disposable coveralls
• Dispose of all asbestos waste at an approved disposal facility in sealed, labelled bags
• Arrange for an independent clearance inspection by a licensed asbestos assessor before the area is reoccupied

All of this is required by law and protects you, your household, and the removalist's workers.

What About Small Amounts — Is There a DIY Exemption?

Under the regulations, there is a limited exemption that allows homeowners to disturb non-friable ACM in their own home in very small quantities, but always check the current threshold and conditions with WorkSafe NZ, but this exemption does not apply to friable asbestos or to work that makes ACM friable — such as chipping, grinding, or cutting. Repointing brick joints by chipping out mortar falls outside any safe DIY exemption. Always check the current rules with WorkSafe NZ or your local council before assuming any exemption applies to your situation.

Protecting Your Home and Family in the Meantime

If you suspect asbestos mortar but haven't had it tested yet:

• Do not disturb it — leave it alone until you have professional advice
• Keep children and pets away from the area
• If mortar is already crumbling, consider temporarily sealing it with an appropriate encapsulant — but discuss this with an asbestos assessor first
• Do not use power tools, angle grinders, or pressure washers near suspected ACM

Building Consent Considerations

Depending on the scope of your repointing or brickwork project, a building consent may or may not be required. Schedule 1 of the Building Act 2004 lists certain exemptions for minor repair and maintenance work, but the rules can be nuanced. Always confirm with your local council whether consent is needed before work begins. Visit MBIE Building Performance for general guidance.

When to Call a Professional

You should contact a licensed asbestos removalist as soon as you suspect asbestos-containing mortar — before any work starts. A qualified asbestos assessor can inspect the site, arrange testing, and advise on the safest approach. A licensed removalist will then carry out the removal legally and safely.

You can find qualified asbestos removal specialists in your area on tradedirectory.co.nz. Always check that any removalist holds a current WorkSafe NZ licence for the class of work required.

Sources & Further Reading

• WorkSafe NZ – Asbestos — regulations, licensing, and guidance for asbestos work in NZ
• MBIE Building Performance — building consent requirements and the NZ Building Code
• BRANZ — research and guidance on building materials including hazardous substances in older NZ homes
• Standards NZ — relevant standards including those referenced in asbestos management
• Tenancy Services – Healthy Homes — obligations for rental properties, including hazardous materials