If you are constructing a new entrance onto a public road, you will need the permission of Council’s Roading Department or the NZ Transport Agency in the case of a State Highway. Both agencies have criteria in terms of suitable sight lines, access separation and minimum construction standards.
If your new house is located on a property currently or formerly used as a vineyard, orchard, market garden, has been subject to historic mining or is close to an old sheep dip or stockyards, then your consent application will be subject to the National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health. A preliminary site investigation report by a suitably qualified professional environmental engineer will be required to assess the risk.
You will be required to install a 30,000 litre storage tank located within 90m of your house that has hardstand access for a fire appliance. A firefighting reserve of 20,000 litres must be maintained at all times.
Flexible water storage bladders. The new exemption means you can place flexible water storage bladders supported on the ground, for irrigation or firefighting purposes up to 200,000 litres in storage capacity without a building consent.
Short-span bridges if they do not span a road or rail area can be built without a building consent. The total span (length) can be a maximum of 6 metres.
Single-storey pole sheds or hay barns in a rural zone with a maximum floor area of 110 square metres can be built without a building consent if:
- the design has been carried out or reviewed by a Chartered Professional Engineer, or
- a Licensed Building Practitioner has carried out or supervised design and construction.
Using polystyrene insulation under concrete slabs
When insulation is installed above a concrete slab, the screed or flooring board that receives the final floor finish is not attached to the building structure, and is therefore considered to be ‘floating’.
The standard method of construction is to install the concrete slab and damp proof membrane (DPM) on the prepared ground. The layer of thermal insulation follows, then a polythene separating layer/vapour control layer (VCL) and floating floor covering.
As long as it offers sufficient compressive strength, almost any type of rigid insulation can therefore be considered, because it is surrounded by two membrane layers, protecting it from ground water, and moisture and alkalis in the concrete slabs and screeds.
XPS insulation provides a flat, strong and dimensionally stable base for the floating screed or flooring board, reducing the likelihood of defects in the floor covering or finish.
The polyethylene does not need protecting. You can poke holes in it, you can puncture it, you can tear it, you can leave gaps in it, and pretty much have your way with it as long as it is in direct contact with the concrete. Huh? But, but, vapor barriers have to be continuous and free from any holes. Actually, no. Air barriers need to be continuous and free from holes, but vapor barriers do not need to be. Lots of vapor moves by air movement, not a heck of a lot of vapor moves by vapor diffusion. The concrete slab is the air barrier, and the ripped and torn and punctured polyethylene sheet is the vapor barrier. It’s that Fick’s Law thing. Diffusion is a direct function of surface area—if I get 95 percent of the surface covered I am pretty much 95 percent effective—and the parts that are left I have filled with concrete which is also pretty good as a vapor barrier. I could wear golf shoes and march around the plastic vapor barrier and not do much damage.
Determinations
MBIE determinations are rulings that provide useful guidance on matters of doubt or dispute about building work. We look at the basics of determinations and, in the subsequent article, the first in a series, at lessons from a determination around compliance of an infinity pool.
DETERMINATIONS ARE legally binding decisions made by the Ministry of Business, Innovation and Employment (MBIE) on matters of doubt or dispute about building work. They must be accepted by building consent authorities for the building work considered in the determination.
They are written so that the discussion and analysis leading to the decision is clearly explained. This means they can be used as guidance by others when faced with similar problems.
What are determinations about?
A determination can be made about:
- whether a building or building work complies with the Building Code
- a council’s decision on:
- a building consent – including time extensions to these
- a notice to fix
- a Code Compliance Certificate – including time extensions to these
- a compliance schedule
- a certificate of acceptance
- granting a waiver or modification of the Building Code
- an exemption from building consent requirements under Schedule 1 – whether or not a building consent is required
- building alterations
- a change of building use
- subdivision of buildings
- dangerous, affected, earthquake-prone and insanitary buildings
- a certificate for public use
- a certificate under section 224(f ) of the Resource Management Act 1991 dams.
What can a determination decide?
A determination can make a decision on whether building work complies with the Building Code. It can confirm, reverse or modify an earlier decision made by the council – for example, a determination may say the council was correct in not issuing a building consent.
A determination can also make waivers or modifications to the Building Code – for example, a determination may modify the time period for which the building must be durable.
It can also make conditions that the council may itself grant or impose – for example, a determination may require the council to issue a building consent with certain conditions.
What do determinations look like?
Published determinations follow a standard format:
- Matter to be determined – the reason the determination has been requested, the matter of doubt or dispute.
- Building work – description of the building work involved.
- Background – what happened that led to the determination.
- Submissions – evidence and correspondence provided by the parties to the determination.
- Discussion – analysis and application of the Building Act and Building Code to the matter in question.
- Decision – the finding of the determination.