It may look just like any other new-build home from the outside, but Fletcher Living's low-carbon home at Waiata Shores holds a plethora of innovative design and technology – enabling it to produce seven times less carbon over its lifetime than a standard Kiwi house.
Thanks to a partnership with Watercare, this home is also designed to achieve a water use target of 75 litres per person per day (L/P/D). This target represents a 53 per cent reduction in current water use in the average Auckland residential home (160L/P/D).
It has features like grey water recycling, large rainwater storage tanks, on-site rainwater treatment, drought-resistant landscaping, a hot water heat pump, a high-WELS-rated dishwasher and washing machine, low-flow showerheads, and low-flow fixtures and fittings.
Watercare customer experience design specialist Ged Campbell says designing a water-efficient home was not as simple as picking a few water-efficient appliances.
"It's not just about one solution, one target or one device – with this being a low-carbon house, everything we did for water efficiency also had to make sense for lifecycle emissions and vice versa. We had to look at the relationship between water user behaviour, and devices as well as the interaction with Watercare's public water and wastewater systems."
One of the home's big innovations is treating and reusing rainwater.
"We have achieved a modelled 80 per cent reduction in potable water demand. To achieve this we had to design big enough rain tanks to capture, store and treat rainwater for potable use. The Hydraloop device, another innovation, is also designed to collect, treat, store and reuse water from showers, baths, and basins for non-drinking purposes.
"Designing rainwater to be used and re-used across the entire home made a big difference to our L/P/D target during modelling."
Interestingly, the best return on investment will come from simple low-flow showerheads. The home is fitted with WELS 4-star-rated low-flow showerheads, with a flow of 5.5 litres per minute.
"We know that showers are where most water is used in a home, and heating the water also uses a lot of electricity, so getting the most water-efficient option for this was a no-brainer,” Campbell says.
His advice for homeowners wanting to be more water-efficient?
“You have to consider the initial investment in buying and installing a device and in maintaining and replacing it over the lifetime of the home, and then conisider the savings on power and water.
“So pick the low-cost devices with the potential for high water and energy-efficiency benefits – like a low-flow showerheads and tapware – and go from there.”
The low-carbon home has smart monitoring with a dashboard designed to gather insights to shift attitudes and behaviour. The home will be tenanted, so Fletcher Living and Watercare can track consumption for three years through a special tenancy agreement.
"We are particularly interested in peak demand periods (summer, morning, and evening), and how smart monitoring can nudge changes to attitudes and behaviour during these times,” Campbell says “because resilience in these peak periods is a driver of infrastructure requirements.”
”As citizens of Auckland we all have a small part to play in reducing lifecycle emissions from the built environment and improving our great city's resilience to adapt to the impacts of climate change.”
