What Is Restricted Building Work in New Zealand?

If you're renovating, extending, recladding or making structural changes to your home, some parts of the project may be classified as Restricted Building Work (RBW).

Restricted Building Work is residential building work that is critical to making a home structurally sound and weathertight. Certain fire-safety design work in multi-unit residential buildings is also restricted.

The important thing for homeowners to understand is that RBW can't simply be completed like ordinary building work. It must be designed, carried out or supervised by appropriately licensed building professionals.

What Counts as Restricted Building Work?

Restricted Building Work generally involves or affects one of three areas:

Your home's primary structure

This is the structure that supports your home and resists loads.

It can include:

• foundations and piles

• floor framing

• load-bearing walls

• structural framing

• beams and columns

• roof framing

• bracing systems.

So if you're removing a load-bearing wall, installing a structural beam, extending your home or making other changes to its primary structure, that work may be RBW.

Your home's weathertightness

This includes building elements and systems designed to keep external moisture out and manage moisture within the building.

It can include:

• exterior cladding and cladding cavities

• flashings and cladding junctions

• some windows, exterior doors and skylights

• roofing

• damp-proofing and waterproofing systems.

This is particularly important with projects such as recladding, extensions and alterations that involve opening or changing the exterior of your home.

Certain fire-safety design

Some fire-safety design work for townhouses and small-to-medium apartment buildings is also Restricted Building Work.

For most owners of standalone homes, however, the two areas you're most likely to encounter are structure and weathertightness.

What Does This Mean for a Renovation or Extension?

Whether work is classified as Restricted Building Work depends on what part of the home is being altered and how the work affects its structure or weathertightness.

For example:

Removing a load-bearing wallChanging the structure supporting your home can be RBW.

Building an extensionAn extension commonly involves foundations, structural framing, roofing and exterior cladding — several areas that can contain RBW.

Recladding a homeRecladding can involve the exterior moisture-management system, including cladding, cavities, flashings and junctions.

Changing windows or exterior doorsWhere the work affects the home's external moisture-management system, it may be RBW.

Converting or altering part of an existing homeIf the work changes structural or weathertightness elements, parts of the project may be restricted.

The important distinction is that not everything within a renovation becomes Restricted Building Work simply because some of the project is restricted.

Your designer and building team should identify which parts of the project are RBW.

Does Restricted Building Work Always Need Building Consent?

No — and this is an important distinction.

Building consent and Restricted Building Work are not the same thing.

Whether work requires building consent depends on the Building Act and applicable exemptions. Whether it is RBW depends on the type of building and whether the work affects specified structural, weathertightness or fire-safety elements.

Since January 2026, for example, qualifying small standalone dwellings of up to 70m² can be constructed without building consent under the granny-flat exemption, but parts of that construction are still Restricted Building Work and require appropriately licensed practitioners.

So don't use “it doesn't need consent” to assume “I don't need an LBP.”

They are separate questions.

Who Can Carry Out Restricted Building Work?

Restricted Building Work must be carried out or supervised by a Licensed Building Practitioner (LBP) who holds the appropriate licence class for that work.

There are different LBP licence classes, including carpentry, roofing, foundations, external plastering, brick and blocklaying, and design.

This matters because being an LBP doesn't automatically license someone for every type of Restricted Building Work.

For example, a practitioner must hold the appropriate licence for the particular RBW they are carrying out or supervising.

Not sure what the different builder qualifications and licences mean? Read our guide to Builder Licences, Qualifications & Associations in New Zealand.

What Is a Record of Work?

This is one of the most important parts of Restricted Building Work for homeowners to understand.

When an LBP carries out or supervises RBW, they must provide a Record of Work (RoW) identifying the Restricted Building Work they personally carried out or supervised.

A copy must be provided to the homeowner and the local council.

If several LBPs carry out different parts of the RBW, each is responsible for recording the work they personally completed or supervised.

For consented work, these Records of Work form part of the documentation required when applying for the project's Code Compliance Certificate (CCC).

A Record of Work doesn't mean the LBP is certifying everybody else's work on the project. It creates a formal record of who carried out or supervised each part of the Restricted Building Work.

What About the Design?

Restricted Building Work can begin before anyone starts building.

Where a consented project contains RBW, the appropriately licensed designer identifies the Restricted Building Work within their design and provides a Certificate of Work as part of the building consent documentation.

Then, during construction, the appropriately licensed tradespeople carry out or supervise their respective RBW and provide their Records of Work.

In simple terms:

Design RBW → Certificate of WorkConstruction RBW → Record of Work

This creates a documented trail of the licensed professionals responsible for the restricted parts of the project.

Why Does Restricted Building Work Exist?

The RBW system exists because mistakes involving a home's structure and weathertightness can have serious and expensive consequences.

These aren't simply cosmetic elements.

A poorly constructed structural alteration can affect how loads are supported through the building. Incorrectly completed cladding, flashings or exterior junctions can allow moisture into areas you can't see.

Requiring appropriately licensed practitioners for this work creates a clear level of competency and accountability around the parts of residential construction where getting it wrong can matter most.

How Do I Know If My Project Includes Restricted Building Work?

If you're planning work involving structural changes, an extension, recladding, roofing or significant changes to the exterior of your home, establish whether RBW is involved before choosing who will complete the work.

You can also check whether the people involved hold the appropriate current licence on the public LBP register. MBIE specifically recommends homeowners check an LBP's ID and register entry before engaging them for RBW.

For projects requiring building consent, your designer should identify the Restricted Building Work during the design and consent process.

The important thing is not to assume that “builder”, “qualified builder” and “Licensed Building Practitioner” all mean the same thing.

They don't.

Restricted Building Work with Alder Homes

Alder Homes undertakes renovations, extensions, recladding and remedial building work across Auckland — projects that commonly involve both structural and weathertightness Restricted Building Work.

Tim Alder is a trade-qualified carpenter and Licensed Building Practitioner, and we work alongside appropriately licensed designers, engineers and specialist trades where required.

If you're planning building work and aren't sure whether your project involves Restricted Building Work, talk to Alder Homes about your project.