Planning a renovation is exciting, but one of the first questions you need to answer is whether your project requires a building consent from your local council. Getting this wrong can lead to fines, problems selling your home, or even being required to demolish unlawful work. Here's a straightforward guide to help you figure out where your project sits.
What Is a Building Consent?
A building consent is formal approval from your local council (or a Building Consent Authority) confirming that your proposed building work complies with the NZ Building Code. It's not just a piece of paper — it triggers inspections during the work and a Code Compliance Certificate (CCC) at the end, which proves the work was done correctly. Without a CCC, you may struggle to sell or insure your home down the track.
Work That Generally DOES Require Consent
As a rule of thumb, if your project changes the structure, weathertightness, or services of your home, it almost certainly needs consent. Common examples include:
- New rooms or extensions — adding floor area or changing the building footprint
- Removing or altering load-bearing walls — structural changes covered under NZS 3604
- New or relocated plumbing and drainage — restricted work under the Plumbers, Gasfitters and Drainlayers Board
- New or altered electrical wiring — restricted work regulated by the Electrical Workers Registration Board
- Decks over 1.5 m above ground level
- Retaining walls over 1.5 m high (or lower if they support a surcharge like a driveway)
- New or relocated wet areas such as bathrooms and laundries (Building Code clause E3)
- Garages, sleepouts, or minor dwelling units
- Re-roofing that changes the roof structure
- Swimming pools (also require fencing under the Fencing of Swimming Pools Act)
If your project involves any of these, contact your local council's building department before you start.
Exempt Building Work — What You Can Do Without Consent
The Building Act 2004 lists categories of exempt building work in Schedule 1. These are low-risk projects where consent is not required, provided the work still meets the Building Code. Common exemptions include:
- Like-for-like repairs and maintenance — replacing a broken window with the same size, repainting, re-roofing with the same material and weight
- Detached buildings under 10 m² that are single-storey, not used for sleeping, and not close to a boundary (conditions apply)
- Internal non-structural work — removing a non-load-bearing wall, installing kitchen cabinetry, laying flooring
- Driveways and paths
- Pergolas that meet specific size and setback criteria
- Heat pumps installed by a registered electrician (the electrical connection is still restricted work)
Important: Exempt does not mean exempt from the Building Code. The work must still comply — it just doesn't need prior council approval. If you're unsure whether a wall is load-bearing, always get a builder or engineer to check.
A Quick Guide: Consent or No Consent?
| Project | Consent Needed? |
|---|---|
| Repainting interior or exterior | No |
| Replacing like-for-like windows | No |
| New bathroom in existing space | Usually yes |
| Removing a load-bearing wall | Yes |
| Building a deck under 1.5 m high | Check with council |
| Adding a sleepout | Yes |
| Installing a heat pump | No (but electrical work is restricted) |
| New kitchen in same location | Usually no |
| Relocating kitchen plumbing | Yes |
| Retaining wall over 1.5 m | Yes |
The Role of Licensed Building Practitioners
Even for consented work, not just anyone can do it. Restricted building work (RBW) — which covers most structural, weathertightness, and foundation work on houses — must be carried out or supervised by a Licensed Building Practitioner (LBP). LBPs must provide you with a Record of Work on completion, which is an important document for your home's file.
Always ask your builder to confirm their LBP licence number and check it on the LBP register.
How to Check for Your Specific Project
- Talk to your local council — most councils offer a free pre-application meeting or have guidance on their website.
- Use the MBIE guidance tool — MBIE Building Performance has detailed guidance on exempt work and the consent process.
- Ask a qualified builder — an experienced builder will quickly tell you whether your project needs consent and can manage the application for you.
- Check BRANZ — New Zealand's building research organisation publishes practical technical guidance for homeowners and tradespeople.
When to Call a Professional
If your project involves anything structural, any changes to plumbing or drainage, electrical work, or alterations to a wet area, you should engage a qualified tradesperson before you lift a hammer. Attempting restricted building work without the right licence is illegal and can void your home insurance.
For structural and general building work, look for a Licensed Building Practitioner. For plumbing and gas, use a registered tradesperson through the PGDB. For electrical work, use a registered electrician through the EWRB.
You can find qualified, vetted local tradespeople — builders, plumbers, electricians and more — right here on tradedirectory.co.nz.