Medium Density Residential Standards

Codewords 109: October 2022

The answer is that you may need an Area of Practice (AoP) 2 Licence if the design work comes within the definition of restricted building work (RBW). The reason why the answer is “may” and not “must” relates to differences in the height limits in the definition of RBW in the Building (Definition of Restricted Building Work) Order 2011 as compared to those in the Medium Density Residential Standards (MDRS).

Clause 6 of the Building (Definition of Restricted Building Work) Order 2011 stipulates:

Certain design work relating to primary structure or external moisture-management systems of residential buildings to be restricted building work

(1) The kinds of design work described in subclause (2) are restricted building work for the purposes of the Act.

(2) The design work referred to in subclause (1) is the preparation of any drawing, specification, or other document, according to which—

(a) the primary structure of a house or a small-to-medium apartment building is proposed to be constructed or altered; or

(b) any external moisture-management system attached to or forming part of a house or a small-to-medium apartment building is proposed to be constructed or altered.

The terms “house” and “small-to-medium apartment building” are, in turn, defined in clause 3 of the Order as:

house means a free-standing, fully detached building consisting of a single residential unit (or a single residential unit and 1 or more residential facilities)

small-to-medium apartment building means a building that—

1. contains 2 or more residential units or residential facilities; and
2. does not contain parts that are neither residential units nor residential facilities; and
3. has a maximum calculated height of less than 10 m.

It is within the last part of the definition of “small-to-medium apartment building” that the differences with MDRS arise as clause 3 of the Order provides the following further definition:

maximum calculated height, in relation to a building, means the vertical distance between the highest point of its roof (excluding structures such as aerials, chimneys, flagpoles, and vents) and the lowest point of the ground

MDRS, however, allows for a maximum building height of 11 metres plus 1 metre for a pitched roof. As can be seen, this exceeds the maximum calculated height provided in the RBW Order.

Given this, a designer will have to be licensed and hold a Design AoP 2 Licence (based on the categories of buildings as defined in the Building (Designation of Building Work Licensing Classes) Order 2010) if the design work comes within the RBW definition. However, if the building is a small-to-medium apartment building which exceeds 10 metres from its highest to lowest points, then it would fall outside of the RBW definition. The design work would not have to be carried out by an LBP.

Caution is, however, still advised even if the design work is not restricted building work.

Firstly, when it comes to disciplinary liability, LBP designers can be responsible and accountable for their work, even if it is not restricted building work. This is because the broadest disciplinary charge under the Building Act is negligence and/or incompetence. The specific charge (section 317(1)(b) of the Building Act) relates to building work, not restricted building work. Building work is defined in section 7 of the Act, and it is much wider than restricted building work, and it would include design work relating to an MDRS structure that was higher than 10 metres.

Secondly, the disciplinary regime focuses on competence. One way of assessing a LBP designer’s competence is by reference to the Area of Practice that they hold as defined in the Designation of Building Work Licensing Classes) Order 2010. Generally, Design AoP 1 licence holders are restricted to Category 1 Buildings, AoP 2 to Category 1 and 2 Buildings, and AoP 3 to Category 1, 2 and 3 Buildings. Interestingly, if you look at the Building (Designation of Building Work Licensing Classes) Order 2010 and compare the height limits in it to the RBW Order you will note that Category 3 Buildings fall outside of the definition of RBW. There may, in this difference, have been an element of future proofing should the definitions of RBW be extended at any time in the future.  

Given the above, if a designer was developing a building consent for an MDRS building that had a high risk-matrix score or was nearing the upper limits in the MDRS allowable height, and they only held a Design AoP 1 licence, for example, then it may follow that they have carried out building work that is outside of their competence. This is another disciplinary charge under the Act (section 314 and 317(1)(h) of the Building Act) and another reason for caution. 

It’s also worth noting that a designer who works outside of their personal competency may run into issues with their professional indemnity cover and their civil liability to their clients.

Finally, remember, the LBP scheme and Areas of Practice are designed to recognise the competence of designers so that consumers can choose the right person for the job. The scheme relies on designers using their licence responsibly to ensure quality compliant homes are built.

See the Building (Definition of Restricted Building Work) Order 2011 and the Designation of Building Work Licensing Classes) Order 2010 here:

Building (Definition of Restricted Building Work) Order 2011 (SR 2011/317) (as at 04 December 2014) Contents(external link) – New Zealand Legislation

Building (Designation of Building Work Licensing Classes) Order 2010 (SR 2010/43) Contents(external link) – New Zealand Legislation

By Faye Pearson-Green, Building Practitioners Board Member

Quiz:

MDRS:

1. What is the maximum calculated height of a small to medium apartment building under the Building (Definition of Restricted Building Work) Order 2011?
   1. Less than 10m
   2. 11m plus 1m for the pitched roof
   3. 10m or higher
2. What is the maximum height under the medium density residential standard?
   1. Less than 10m
   2. 11m plus 1m for pitched roof
   3. 10m or higher
3. How is ‘maximum calculated height’ measured under the Building (Definition of Restricted Building Work) Order 2011?
   1. The vertical distance between the upper surfaces of the floors of the lowest and highest storeys
   2. The vertical distance from the lowest storey floor to the upper-most ceiling in the building
   3. The vertical distance between the highest point of its roof (excluding structures such as aerials, chimneys, etc.) to the lowest point of the ground