While granny flats may soon be exempt from consent, homeowners still need to be mindful of site coverage regulation in their area. Here’s how Permcon permeable concrete can help!
While granny flats may soon be exempt from consent, homeowners still need to be
mindful of site coverage regulation in their area. Here’s how Permcon permeable
concrete can help!
Did you know that new rules have been proposed to allow small, self-contained, detached houses of up to 60m2 to be built on a property with an existing home on it, without requiring a building or resource consent?
In June, RMA Reform Minister Chris Bishop and Deputy Prime Minister Winston Peters announced the plan to amend the Building Act and Resource Management Act. At the time, Peters said:
“Over a quarter of households that do not own their home spend more than 40% of their income on housing. High housing costs have a greater impact on Māori, Pasifika, and people with disabilities, as well as seniors – so unlocking the space in the backyards of family members opens the door to new ways of living.”
Bishop said the initiative fits within the Government's wider package of work to ‘streamline’ the building consent system and address the housing crisis through its ‘Going for Housing Growth’ agenda.
Site coverage rules remain
While the proposal could allow contractors to build small, self-contained, detached houses (officially known as an MRU or multi residential unit) without consent, there are still regulations regarding site coverage to adhere to. Site coverage rules in New Zealand vary by region but, generally, the maximum percentage of a site that can be covered by impermeable surfaces is about 70%. Of that, buildings can account for between 30% and 50%.
While the MRU proposal included the possibility of increasing the allowable site coverage for buildings to 50%, 60% or 70%, it did not suggest any change to the limit on impermeable surfaces.
This means that if the maximum 70% of the allowable impermeable surface area of a site is
occupied by buildings, then driveways and other covered areas would need to be permeable.
Permcon NZ director Stuart Girvan points to permeable concrete as one potential solution.
“Using a product such as Permcon permeable concrete, we can convert a significant percentage of a property’s hard surface to a permeable area, allowing homeowners the flexibility to develop an MRU while still meeting their local council’s District Plan standards.”
Girvan adds that landscapers should make sure to stay up to speed with the incoming regulations, and any local ones, that might prove useful when discussing requirements with clients.
“Many councils also require minimum areas of a developed site to be covered with grass
or plant as well, so it pays to be able to talk your client through those and make sure their plans are in line with regulations – whether they need a consent or not,” said Girvan.
Why use Permcon?
Permcon permeable concrete produces a hardwearing, pervious surface that allows stormwater to pass through the top course and into the open grade basecourse beneath. This allows stormwater to replenish the natural ground aquifer or be discharged to the stormwater network via under drains in a measured and controlled manner, reducing the peak flows of a storm event.
As such, permeable concrete pavements help reduce street flooding, improve the health of
receiving streams and rivers by filtering debris and pollutants from the stormwater, and cool water as it infiltrates the permeable base system.
In addition, all Permcon installers are certified by Permcon and the permeable driveway comes with a Producer Statement 3 – documentation which confirms the installation was conducted correctly and the driveway will last for the intended duration.
