Greens is an unusual company. Started in 1935 during the Depression by Peter Green, now a sprightly 97, the company still conducts the majority of its business in New Zealand, at its Hamilton plant.

“We are very different to other manufacturing or tapware companies,” says John, Peter’s son, who triggered the company’s expansion from metal pressing into tapware in 1978.

“A lot of manufacturing in NZ has shut down and gone offshore – we have not done that. We do a bit of sourcing from overseas – but we source components from all over the world.

“In 1978 we started the design and development for the tapware,” says John.

“At that time there was a monopoly in NZ. We came in and rocked the boat and it’s been rocking ever since.

“Our expertise is in water conservation, temperature control and safety and covering all pressure situations. There’s a lot of strange things happen in plumbing systems and we have solutions for those.”

The tapware division these days is many times larger than the stamping and metal pressing.

Research and development and independent testing are the secrets to the company’s longevity. John has an engineering background and set out to understand all aspects of the functionality and ergonomics of taps, particularly single-lever taps – the company’s signature product.

“We don’t believe it’s worth designing a product that is the same as everyone else’s,” says John.

“There must be some design feature that gives a benefit either in ergonomics, performance, looks or a combination of the whole lot.

John travels the world looking for difficult plumbing situations, which I see as opportunities. I bring the ideas back and we engineer solutions to those problems.”

Over the years John has built up a database of research and know-how from all over the world gleaned from industry connections and allies with whom he compares notes when they’re not in direct competition.

One of the fruits of his years of research and development has been the Green’s cartridge. The cartridge contains an internal ceramic valve mechanism to control the flow and temperature of the water through a mixer tap.

The cartridge can adjust the flow to account for low pressure and unequal pressure between hot and cold water and thus combat some of the problems arising from the installation of mandated products under the WELS scheme such as flow restrictors and other water saving devices.

“When flow restrictors are placed onto shower mixers, you get a lot of back pressure and it destroys the mixer's ability to adjust the temperature because there’s so much pressure in the water,” John says.

“It affects the shower mixer’s ability to act as a temperature control device.

“We have adjustments in the product to remove or eliminate the back pressure, allowing the installer to adjust the flow accurately, even in a difficult situation, providing a smooth temperature control,” John says.

“Other products may struggle with temperature adjustment.”

“We’ve developed and upgraded the cartridge over the years so that today we would be world leaders in that type of technology,” says John.

“We’ve developed it in-house with different technological connections around the globe in terms of the componentry.

“We also have a team of engineers – for years we’ve put a lot of effort into research and development because we see that as where our future is.”

Greens also has a UK office and a lot of experience in the UK, where gravity systems are used; 60-70% of the systems in the UK have a tank in the ceiling, relying on gravity to supply the hot water.

“You only get about 4psi, less than 30kpa on the hot water, whereas you have mains pressure cold – so there’s a very uneven pressure between the two temperatures,” says John.