Hi Spud,

In short, judging by the scope of the work you have outlined, a building consent will not be required.

Check out the MBIE Building Act 2004 Schedule One Guidance document on work that does not require a building consent (link below)

http://www.dbh.govt.nz/UserFiles/File/Publications/Building/Guidance-information/pdf/building-work-consent-not-required-guidance-3rd-edition.pdf

Specifically check out exemptions 34 - Minor alteration to drains & 35 - Alteration to existing sanitary plumbing (excluding water heaters).

Exemption 34 states that Minor alterations to existing private drainage does not require a building consent, provided that:
1. Alteration to drains for a dwelling if the alteration is of a minor nature, for example, shifting a gully trap.
2. Subclause (1) does not include making any new connection to a service provided by a network utility operator.

This exemption only relates to dwellings and enables an authorised person to alter existing private drainage without needing a building consent. This sort of building work usually occurs during alterations to existing bathrooms, kitchens, laundries or toilets.  New connections to public drainage are specifically excluded from this exemption.


Exemption 35 states that alterations to existing sanitary plumbing in a building does not require a building consent, provided that:
1. (a)the total number of sanitary fixtures in the building is not increased by the alteration; and
    (b)the alteration does not modify or affect any specified system.
2. Subclause (1) does not include an alteration to a water heater

Any plumbing work under this exemption must be carried out by an authorised person, otherwise it is not exempt work. Where sanitary plumbing work could adversely affect the structural performance of structural elements such as floor joists or wall framing, this work may require a building consent. If you are not sure, we recommend seeking professional advice first (eg from a licensed building practitioner, chartered professional engineer, registered architect, building consultant, registered building surveyor or accredited building consent authority)



A key trigger for the requirement for a building consent is increasing the total number of sanitary fixtures within a building.

In this instance if you are deleting a bath and adding a toilet then there is no increase in the total number of fixtures so the work can be carried out without a building consent by an authorised person under Schedule One of the Building Act 2004.

Friends of mine were having a sleepout built and inspected by Council Inspector. It was a hot day and he asked for water so she invited him inside. At the time they were having a new kitchen installed. The inspector noted that the position of the kitchen sink had moved and informed them that he was issuing a stop work until they had uplifted a consent for the work in the kitchen and laundry.   Moral of the story is to check with the Council. Second moral is - it will always be the plumbers fault. Local by laws and the building act are written in such a way that the onus is on whoever did the work to find out. Do not believe the homeowner unless they have it in writing

There was holes in the floor where the old wastes had been. I can assure you the air was blue that day.

All this shows me is that the people writing these laws are fools.
I think we all know that shifting a sink is a hell of a lot less work or potential problem than digging up drain, cutting into it and installing a toilet.
What do they base their justifications on for these requirements? The amount of water a house flushes down a drain?

I'm confused.

I agree with you. Don't trust anyone. Get it in writing.