Under the rain: harvesting rainwater at home - Building NZ
Under the rain: harvesting rainwater at home

Under the rain: harvesting rainwater at home

Utilising a free, natural resource is more uncommon in our cities than it should be. We spoke to Tanksalot about the benefits of collecting rainwater and how to avoid relying on council-supplied water altogether...

Words by ArchiPro Editorial Team

Water tanks - both retention and detention - are rising in popularity as more people look to utilise rainwater rather than relying on council-supplied water. However, until recently the norm had become plastic tanks; tanks which required the addition of a host of chemicals to ensure they were durable in the outdoors for long periods of time, Tanksalot’s Vicki Niethe says.

“People are moving well away from plastic now, and looking at sustainable alternatives. That’s where our corrugated steel tanks provide a viable and fully recyclable option. Due to the strength and durability of corrugated steel, there is no need for the addition of chemicals such as UV stabilisers.”

Tanksalot’s steel water tanks all have a 20-year corrosion warranty, and a 10-year manufacturer’s warranty. Aside from the ability to recycle the tanks at the end of their use, they have a host of benefits including the reduction of water charges related to the use of council water supplies, and the ability to sustainably manage stormwater runoff.

In terms of the former, the collection of rainwater in a tank used for drinking and all household water needs can equate to significant cost savings over a year, Vicki says. “People are using more water than they ever have before, with the average New Zealander now using approximately 200 litres of water every day.

“Installing a rainwater tank is a simple way to utilise a natural resource for free. It’s also important in the event of a natural disaster or emergency. Having a natural water supply in the home in the event council systems were damaged is an important part of adequately preparing for a disaster.”

Detention tanks on the other hand offer a different benefit. “The way we are building to higher densities means there are less permeable surfaces on the land. That means the stormwater runoff from the roofs of high density properties emit significant amounts of water into stormwater drains. “In some areas, incorporating a retention tank when embarking on a new build or renovation in which a building’s footprint is extended, a detention tank is a requirement,” Vicki says. Detention tanks are designed to hold stormwater runoff from roofs and release it slowly into the drain, thereby reducing pressure on stormwater infrastructure.

Tanksalot has specialised in corrugated steel detention and retention tanks for more than ten years. A core part of their service is the ability to offer fully customisable tanks, designed for individual project requirements. “Once a tank is ordered, it will be made to the required dimensions and all required fittings will be incorporated including the inlet, outlet and overflow,” Vicki says. “Once delivered to site it is a quick and easy process to install.

“Consent is not required to install water tanks on a property however where requirements exist to have a minimum of 40 square metres of usable outdoor space on a section and water tanks are installed, there may be council requirements if the tanks are higher than the fence or take up the majority of the available permeable space,” Vicki says.  

“All tanks are above ground tanks and have to be on a level and compact site. However they can be placed on a roof or deck provided the right support is in place to hold their weight. The base needs to compensate the weight of the tank. For example, a 1000-litre tank is equivalent to one tonne of water.”


If you’re considering the addition of a water tank, or require one as part of a new build or renovation, make sure you visit Tanksalot on ArchiPro here to find out more about the options.


Or read more about water tanks: Under the rain: harvesting rainwater at home



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