In New Zealand, not all building work is created equal. Some work on homes is legally classified as restricted building work (RBW), meaning it must be carried out or supervised by a Licensed Building Practitioner (LBP). Understanding the difference protects your home, your family, and your investment.
What Is a Licensed Building Practitioner?
An LBP is a tradesperson who has been assessed and licensed by the Ministry of Business, Innovation and Employment (MBIE) to carry out or supervise restricted building work. There are several licence classes, including carpenters, designers, roofers, brick and blocklayers, external plasterers, and site licence holders. Each class covers specific types of work, so it's important to check that the LBP you hire holds the right licence class for your project.
What Is Restricted Building Work?
Restricted building work (RBW) is work that affects the structural integrity or weathertightness of a home, or relates to fire safety systems. The idea is that these are the areas where poor workmanship poses the greatest risk to occupants and the building itself.
RBW applies to residential buildings (houses and small multi-unit dwellings) and generally includes:
- Structural work — framing, foundations, load-bearing walls, beams, and connections that are part of the primary structure
- Weathertightness work — installing or altering the building envelope, including roofing, cladding, windows, and external doors where they affect weathertightness
- Design work — producing plans and specifications for the above, if a building consent is required
- Site work — supervising and coordinating the above on site
Work that is not restricted building work — such as interior fit-out, cabinetry, decking (in many cases), fencing, and non-structural alterations — can generally be done by any competent tradesperson or a capable homeowner, subject to consent requirements.
When Is a Building Consent Also Required?
RBW almost always goes hand-in-hand with needing a building consent from your local council. However, some work is exempt from consent under Schedule 1 of the Building Act 2004. Even if work is consent-exempt, if it is still classified as RBW, an LBP must carry it out or supervise it.
Always confirm with your local council whether your specific project needs a consent and whether it involves RBW — rules can vary and the details matter. You can find general guidance at MBIE Building Performance.
Common Examples of Restricted Building Work
| Type of Work | Likely RBW? | Notes |
|---|---|---|
| New house construction | Yes | All structural and weathertightness elements |
| House extensions or additions | Yes | Structural framing and cladding |
| Re-roofing (full replacement) | Yes | Weathertightness |
| New windows or external doors | Often yes | If affecting weathertightness |
| Load-bearing wall removal | Yes | Structural integrity |
| Foundation repairs or replacement | Yes | Structural |
| Interior non-structural walls | No | Generally not RBW |
| Decks under 1.5 m high | Often no | Check with council |
| Kitchen or bathroom fit-out (non-structural) | No | But plumbing/electrical are separate restricted trades |
What About Electrical, Plumbing, and Gas Work?
It's worth noting that electrical, plumbing, gasfitting, and drainlaying are governed by separate licensing regimes — not the LBP scheme. These trades have their own restricted work rules:
- Electrical work must be done by a registered electrician under the Electrical Workers Registration Board (EWRB)
- Plumbing, gasfitting, and drainlaying must be done by a licensed tradesperson registered with the Plumbers, Gasfitters and Drainlayers Board (PGDB)
Never attempt restricted electrical or gas work yourself — the safety risks are serious and the legal consequences significant.
What Happens If RBW Is Done Without an LBP?
If restricted building work is carried out without a licensed practitioner, you could face real problems:
- Difficulty selling your home — buyers and their lawyers will check LBP records
- Insurance issues — your insurer may decline claims related to unlicensed work
- Council compliance issues — the council may require remediation before issuing a code compliance certificate
- Personal liability — if the work causes harm or damage
LBPs are required to provide Record of Work documents at the end of a job, which form part of your home's building file. Keep these safe.
What Can Homeowners Do Themselves?
Homeowners can carry out some building work on their own home without an LBP, provided it is not restricted building work and any required consents are obtained. This might include painting, tiling, non-structural interior work, and some minor repairs. However, if you're unsure whether your project touches on RBW, always check with your council or consult an LBP before starting. BRANZ also publishes useful guidance on building standards and best practice.
When to Call a Professional
If your project involves the structure, roof, cladding, or weathertightness of your home — or if a building consent is required — you should engage a qualified LBP. You can verify that a tradesperson holds a current LBP licence by searching the public register at lbp.govt.nz. Qualified local carpenters and builders who hold LBP licences can be found right here on tradedirectory.co.nz.
