Understanding what building work you can legally do without a consent in New Zealand can save you time and money — but getting it wrong can cause real headaches when it comes time to sell your home or make an insurance claim. The rules are set out in the Building Act 2004 and its schedules, and they're worth knowing before you pick up a hammer.
The Basics: What Is Exempt Building Work?
Not all building projects require a building consent from your local council. The Building Act 2004 lists categories of exempt building work in Schedule 1. These are projects considered low-risk enough that a consent isn't required — but that doesn't mean there are no rules. The work must still comply with the NZ Building Code, and in some cases must be carried out or supervised by a licensed professional.
MBIE Building Performance publishes detailed guidance on Schedule 1 exemptions, and it's the best first stop before starting any project.
Common Projects That Don't Need a Consent
Here are the types of work that are generally exempt, provided they meet the conditions set out in Schedule 1:
- General repair and maintenance — like-for-like replacement of cladding, roofing, windows, or linings (same materials, same location)
- Painting and decorating — interior and exterior, including plastering small areas
- Driveways and paths — ground-level concrete or paving work
- Detached single-storey buildings under a certain floor area (e.g. a garden shed or small sleepout), subject to size and setback limits
- Retaining walls up to 1.5 m high (where they don't support a surcharge such as a driveway or building)
- Fences up to 2.5 m high (not swimming pool fences, which have their own rules)
- Decks that are low to the ground (generally no more than 1.5 m above ground level) and meet structural requirements under NZS 3604
- Internal non-structural work — removing or adding non-loadbearing walls, replacing kitchen or bathroom fittings (plumbing connections aside)
Important: Even exempt work must comply with the Building Code. If you're unsure whether a wall is loadbearing, get a carpenter or structural engineer to check first.
What You Can DIY vs. What Needs a Licensed Pro
Being exempt from consent doesn't mean anyone can do the work. Some tasks within an exempt project are restricted building work (RBW) or involve licensed trades.
| Type of Work | DIY OK? | Licensed Pro Required? |
|---|---|---|
| Painting, tiling, flooring | Yes | No |
| Replacing a like-for-like window | Generally yes | Check if RBW applies |
| Structural framing (loadbearing) | No | Yes — LBP Carpenter |
| Roof cladding on a house | No | Yes — LBP Carpenter |
| External wall cladding | No | Yes — LBP Carpenter |
| Electrical wiring | No | Yes — registered electrician |
| Gas fitting | No | Yes — licensed gasfitter |
| Plumbing connections | No | Yes — licensed plumber |
Restricted building work covers structural and weathertightness elements of homes and small buildings. It must be carried out or supervised by a Licensed Building Practitioner (LBP). This includes things like structural framing, external cladding, roofing, and bricklaying on residential buildings.
Electrical, Plumbing, and Gas: Always Use a Licensed Trade
Regardless of whether a building consent is needed, electrical, plumbing, and gasfitting work is legally restricted in New Zealand.
- Electrical work must be done by a registered electrician (registered with the EWRB). Homeowners can do very minor work like replacing a light fitting or socket cover, but any wiring work must be inspected and certified.
- Plumbing and drainlaying must be carried out by a licensed plumber or drainlayer registered with the PGDB.
- Gasfitting is also restricted — never attempt gas work yourself.
⚠️ Safety note: Unlicensed electrical or gas work is not only illegal — it can be fatal. Always use a licensed tradesperson for these tasks.
Special Cases to Watch Out For
Swimming Pools and Fencing
Pool fencing is governed by strict rules under the Building Act. All pool barriers must comply with NZS 8500 and generally require a consent and inspection.
Sleepouts and Minor Dwellings
A small sleepout may be exempt if it meets size thresholds and doesn't have sanitary facilities, but the rules are specific. Check with your council and MBIE before proceeding.
Heritage Buildings and Overlays
If your home is in a heritage overlay or special character zone, your local council may have additional requirements even for otherwise exempt work.
Weathertightness
NZ's variable climate — especially in wetter regions like the West Coast, Northland, and Wellington — means weathertightness is critical. BRANZ provides excellent technical guidance on cladding and moisture management that's worth reading before tackling any exterior work.
When to Call a Professional
Even when work is technically exempt and you're handy with tools, there are good reasons to bring in a qualified tradesperson:
- The work involves loadbearing structure or affects the weathertightness envelope
- You're not confident the finished result will meet the Building Code
- You want documentation for future sale or insurance purposes
- The project is larger or more complex than it first appeared
A good local carpenter, builder, or specialist tradesperson can also advise you on whether consent is actually needed — saving you from costly mistakes. You can find qualified, vetted tradespeople in your area at tradedirectory.co.nz.