If you're planning a building project in New Zealand, one of the first things you need to understand is whether your work falls under the category of restricted building work (RBW). Getting this wrong can create serious legal, insurance, and safety headaches — so it pays to know the rules before you pick up a hammer.
What Is Restricted Building Work?
Restricted building work is building or design work that affects the structural integrity or weathertightness of a home, or involves certain safety-critical systems. Under the NZ Building Code, this work must be carried out or directly supervised by a Licensed Building Practitioner (LBP) — a tradesperson who holds a current licence in the relevant licence class.
The rules are set out in the Building Act 2004 and administered by MBIE Building Performance. The intent is to ensure that the parts of your home most critical to keeping it safe, dry, and structurally sound are handled by someone with proven competence.
What Work Is Restricted?
Restricted building work generally covers:
- Structural work — foundations, framing, load-bearing walls, beams, and columns in houses and small-to-medium apartment buildings
- Weathertightness (cladding) work — installing or repairing external cladding systems such as brick veneer, plaster systems, or fibre cement products like those from James Hardie
- Roofing — roof framing and the installation of roof coverings on residential buildings
- Design work — architectural or engineering design that relates to the structural or weathertight elements of a home, where building consent is required
- Certain passive fire systems — fire-rated construction in residential buildings
As a guide, if your project requires a building consent and touches the structure or the building envelope, there's a strong chance it involves restricted building work.
Who Can Do Restricted Building Work?
Only an LBP (Licensed Building Practitioner) can carry out or supervise restricted building work. LBPs are licensed in specific classes, including:
| Licence Class | What It Covers |
|---|---|
| Design | Structural and weathertight design |
| Carpentry | Structural framing, roofing, cladding |
| Roofing | Roof coverings and associated work |
| External Plastering | Plaster-based cladding systems |
| Brick and Blocklaying | Masonry cladding and structural masonry |
| Site | Overall site supervision of RBW |
You can search the public register on the LBP website to verify that your builder or tradesperson holds a current, valid licence before work begins.
What Happens After the Work Is Done?
Once restricted building work is complete, your LBP must provide you with a Record of Work — a formal document confirming they carried out or supervised the work. This is submitted to your local council alongside the code compliance certificate (CCC) application. Without it, your council may not issue a CCC, which can cause major problems if you ever sell or refinance your home.
What Can Homeowners Do Themselves?
Not everything requires an LBP. Owner-builders can carry out restricted building work on their own home under a specific exemption — but only if:
- The work is on a home you own and intend to live in
- You are not doing it for payment or as part of a business
- You apply for an owner-builder exemption through your local council
Be aware that if you sell the home within ten years, you must disclose that owner-builder work was carried out, which may affect your sale. BRANZ has useful technical guidance on building standards and best practice if you're taking this route.
For work that does not require building consent and does not affect structure or weathertightness — such as painting, tiling, replacing kitchen cabinets, or basic landscaping — homeowners can generally get stuck in themselves.
Electrical, Plumbing, and Gas Work
It's worth noting that electrical, plumbing, gasfitting, and drainlaying are governed by separate legislation and are also restricted to licensed professionals:
- Electrical work must be done by a registered electrician (see EWRB)
- Plumbing, gasfitting, and drainlaying must be done by a licensed tradesperson registered with the PGDB
Safety note: Never attempt restricted electrical or gas work yourself. The risks include fire, electrocution, gas explosion, and voided insurance — and unlicensed work is illegal.
When to Call a Professional
If your project involves any of the following, you should engage a qualified, licensed tradesperson:
- Any structural alterations or additions to your home
- Re-roofing or replacing cladding
- Building a new deck over a certain height (check with your council)
- Any work requiring a building consent
- Anything you're unsure about
Hiring the right professional protects your home, your family, and your investment. You can find qualified, local LBPs and other tradespeople on tradedirectory.co.nz.