Exempt building work – part 2

By - , Build 161

Part 1 of this series in the last Build covered off the basics of exempt building work and some of the easy to measure exemptions. In part 2, we go into a few of the more complex exemptions.

AS A BRIEF recap, all building work requires a building consent except for work exempted under Schedule 1 of the Building Act 2004. Schedule 1 lists the building work that does not require a building consent.

MBIE has issued guidance on Schedule 1 with helpful and practical examples – see Guidance: Building work that does not require a building consent.

Check to see if you need a consent

Don’t forget to check if you need a building consent. This will help you avoid fines from councils or penalties from the Building Practitioners Board. You can check by reading the MBIE guidance and contacting your local building consent authority.

Exemption 8 – replacing windows and exterior doorways in existing dwelling and outbuilding

All work in connection with a window (including a roof window) or exterior doorway in an existing dwelling or outbuilding of not more than 2 storeys in height is exempt work.

However, if you are replacing a window or doorway, that item must not have failed its durability test under clause B2 of the Building Code. Based on the current Code, this means that the existing item that is being replaced must have satisfied the not less than 15-year durability requirement.

You will need a building consent if the item needs replacing within 15 years of installation or if the building work modifies a specified system such as when installing a roof window results in repositioning a sprinkler head.

This exemption covers structural and weathertightness work as long as the purpose of that work is to install the window or exterior doorway.

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Exemption 11 – changing internal walls and doorways in existing building

Changing an internal wall or doorway is exempt building work unless the wall is:

  • loadbearing
  • a bracing element
  • a firewall – a barrier designed to limit the spread of fire, heat and structural collapse
  • part of a specified system such as electromagnetic or automatic doors
  • made of units of materials stacked or bonded together with mortar such as bricks or blocks.

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Exemption 12 – replacing internal linings and finishes in existing dwelling

You can replace any interior linings without using comparable materials in an existing dwelling without needing a building consent.

Interior linings could be part of bracing or fire-resistant elements, so we suggest investigating and installing the appropriate type of replacement lining.

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Exemption 13 – installing thermal insulation

You don’t need a building consent to install thermal insulation in an existing building unless you are installing it in an exterior wall or an interior firewall.

Installing insulation in ceilings, floors and interior walls that are not firewalls are examples of exempt work.

Under the Residential Tenancy Act, ceiling and underfloor insulation will be compulsory in all rental homes from 1 July 2019. You can read more about this requirement on the tenancy website.

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Exemption 14 – creating penetrations

Penetrations that are 300 mm or less in diameter can be made through both internal and external building components without a building consent for:

  • detached dwellings of any height and dwellings within a building that is not more than 3 storeys high
  • outbuildings that are detached and not more than 3 storeys high
  • all other buildings as long as doing so does not modify or affect:
    • the primary structure
    • any specified system.

These exemptions include any associated building work like weatherproofing or fireproofing.

For other scenarios such as a commercial building, creating a penetration not exceeding 300 mm in diameter is still exempt building work if it does not affect the primary structure or a specified system such as a fire suppression system.

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Exemption 35 – altering existing sanitary plumbing (excluding water heaters)

Alterations to sanitary plumbing fixtures such as baths, showers and basins are exempt from building consent requirements as long as:

  • the number of fixtures in the building is not increasing
  • the alteration does not affect a specified system such as fire sprinklers.

This work must be done by an authorised person (see page 79 of MBIE’s guidance). It also excludes work for water heaters, although this work may be covered by other exemptions.

Next time – the trickiest exemptions

The next article in our exempt building work series will cover off the trickiest exemptions you’re likely to encounter. Stay tuned.


1. If you go to quote for a client to install a window in their 2-storey home, would you need to price in the cost of a building consent?

a. Yes, you need a building consent because the dwelling is 2 storeys.

b. No, as long as it wasn’t installed less than 15 years ago and hasn’t leaked or rotted.

2. Is work to remove my exterior wall exempt if I am removing it to extend my lounge over my deck?

a. You need to get a consent because it’s an addition and it doesn’t fit within any of the exemptions of Schedule 1.

b. Yes, as long as it is not a firewall.

c. It doesn’t require a consent because it’s a deck.

3. I want to change my tongue and groove kitchen floor to plywood with a floating floor over it. I also want to install insulation beneath the floor. Can I do this all without a building consent?

a. Only if the floor is not a bracing element.

b. No, you can’t start without a building consent.

c. Yes, it is exempt work.

d. You can’t install the insulation without a building consent.

4. I’ve been asked to install a heat pump on a brick veneer but I only have a carpentry licence. Can I do this without a building consent?

a. You need a brick and blocklaying LBP licence for that but not a building consent.

b. You need a building consent and a brick and blocklaying LBP licence.

c. You don’t need a building consent, but you need to be a registered electrical worker to do that work!

5. I am a roofing LBP and I want to cut a roof vent into an existing roof. How big can it be before I need a building consent?

a. You’re licensed as a roofer – you don’t need any building consents.

b. 300 mm in diameter.

c. 100 mm in diameter.

a. 500 mm in diameter.


1. b 2. a 3. c 4. c 5. b

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For more

The guidance document is available on MBIE’s Building Performance website at https://tinyurl.com/y7mjnp4r. Information on the requirement for ceiling and underfloor insulation is available at www.tenancy.govt.nz/maintenance-and-inspections/insulation. Click here to read part 1 of this article.

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Articles are correct at the time of publication but may have since become outdated.