This year the family foundation celebrates 20 years since its first donation. Over that time it has given away $135million.
"We wanted to be able to share what we had with other people," said Sir Stephen. "We had a conversation and decided that's what we're going to do with this [money] - it was far too much for us to spend ourselves."
Mrs Tindall, one of 10 children, had been engaged in community work since her teenage years.
"We were a big family, but through the church mum and dad always encouraged helping other people. It was quite a natural thing." She met her future husband at a Rotary Club Leadership Awards ceremony, and the pair married in 1973.
She has volunteered weekly for 21 years at Northcote's De Paul House, which provides families in need with a place to stay and learn. When she began, her youngest son Ben was only 4, and got dragged along too.
Since 2007 the foundation has donated $1.36 million to De Paul House, and Mrs Tindall, a trained midwife, has donated thousands of hours.
She leans forward and speaks animatedly about it.
"I really love it - I love working with the mothers and the fathers and the children, and we can look after the children while the parents go to classes." In 1995, the foundation's first donation of $2326 went to Auckland Teachers' College out of an asset base of about $1.5 million.
"We started very low key and we got inundated with applications from all over," Mrs Tindall said. "We were all learning on the job, really. We had one staff member and a board, and piles of applications to go through." Dividends from Mrs Tindall's shares in The Warehouse have enabled the Tindall Foundation to give nearly $62 million to organisations supporting families and social services. Last year, the Tindall Foundation gave away $9,560,966 and committed another $11,188,759 to various organisations, mostly within New Zealand, from a total asset base of $183,727,977.
When it was first set up, Sir Stephen did a television interview. Afterwards the foundation was overwhelmed with requests from people wanting money to build extensions and new decks on their houses.
Sir Stephen said from the beginning he and Mrs Tindall were keen to place the money back into the communities in which Warehouse stores were situated, and they now use local funding managers to do so.
Sir Stephen speaks passionately about a health science academy set up by the Counties Manukau District Health Board to encourage Maori and Pacific students to train as medical professionals. His wife and their eldest daughter Elizabeth - who sits across a table from her parents - join in and it becomes hard to discern who is saying what.
The Tindalls are a tight-knit family. Elizabeth works as the foundation's communications adviser, as does their daughter Kate. Their eldest son Rob is a trustee.
Mrs Tindall says Sir Stephen likes "bigger picture" projects, and agrees when he says she is passionate about smaller things.
"The projects that don't get seen," she says. "Small local groups that are just doing great work with families - like parenting courses or budgeting." The foundation now has seven staff and five trustees, plus about 18 funding managers working around New Zealand. The five Tindall children are beginning to take on philanthropy themselves. Says Sir Stephen: "We love it."
On Wednesday night, the Tindall Foundation celebrated its 20th anniversary with an event hosted by Governor-General Sir Jerry Mateparae at Auckland's Government House. Five recognition awards were presented to organisations that had been assisted by the foundation for their dedication to communities.
Space NZ Trust
Space NZ Trust offers parenting and child development programmes.
The trust was established by Lower Hutt Playcentre mums Leanne Dawson, Truus Dingemanse and Sue Pattinson in 2003 to support first-time parents.
"We saw there was a real gap in the community for first-time parents and their babies, and it's a time of transition for a parent," Ms Pattinson said.
"It's also a time when parents feel isolated, so it was to bring them together over a time to connect with other parents and have a place to discuss what it's like to become a parent."
Ms Dingemanse said the programmes helped create networks within communities for parents and their children.
Ms Dawson added: "There were a lot of parenting programmes on offer at the time we started, but there was nothing that was specifically targeting first-time parents."
The Tindall Foundation helped the group expand, and today more than 300 programmes are delivered to 8000 parents and their babies each year by 55 partner organisations across New Zealand.
Group sessions are held weekly in community venues and early childhood centres. Sessions bring together parents and children, encourage discussion and play, and provide equipment to support babies' learning.
Mountains to Sea
Mountains to Sea is an education trust that sets up programmes to teach children across New Zealand about marine and freshwater conservation.
Through the work of founding trustee Samara Nicholas, it has created two underwater education programmes - Experiencing Marine Reserves (EMS) and Whitebait Connection - to enable kids to see the wonders of marine and freshwater life.
Last summer, EMS hosted 27 marine community engagement events across New Zealand. Ms Nicholas said she helped establish a marine reserve in Whangarei Harbour when she was at high school.
"I fell in love with the idea that we can make a difference," she said.
In 2002, she started the trust and now EMS events are run all over the country educating children and their parents about marine reserves.
"We need more of them, but that can't happen without more public support, which is what we focus on."
Acorn Foundation
Tauranga lawyer Bill Holland helped to establish Acorn Foundation - an organisation that encourages people to donate and invest endowment funds.
As a trustee, Acorn pays a percentage of earnings to a community group of the donor's choice. Since its establishment in 2003, more than 220 people in Tauranga have donated money that will benefit the Western Bay of Plenty.
Acorn has more than $12 million invested and will distribute more than $500,000 this year to a range of community groups - such as Red Cross, the Otanewainuku Kiwi Trust and the Tauranga Bay of Plenty Hearing Association.
"Most people I know like to think they'll make a difference in their lives," Mr Holland said.
Many Kiwis gave time rather than money, but Acorn encouraged people to leave a small percentage in their will to the foundation.
He said it could be a little, or a lot.
"One of our funds we have came from a hospital cleaner. It's not just for rich people."
He said the fund was already making a profound difference in the community, and it would not exist if not for Sir Stephen Tindall and the Tindall Foundation.
Mr Holland is also chairman of Community Foundations of New Zealand, which started in 2012 to help establish and promote community foundations around the country. Nationally, New Zealand's 13 Community Foundations have more than $40 million under management and more than $160 million in expected funds.
Project Lyttelton is an organisation that works to help Lyttelton become a strong community. Chairwoman Margaret Jefferies and her team provide a range of services including a farmers' market, seasonal festivals, a community garden, a children's garden and a "timebank", a way of trading skills in the community.
Ms Jefferies, who has been a fulltime volunteer for the last 11 years, said the vision was to create a "sustainable community". She brought the timebank concept to New Zealand about 10 years ago. "In its simplest form, it's swapping skills." Everyone's time is equal, so an hour's gardening could earn an hour's house painting.
About 670 members are signed up in a community of 3000. "I like to think of it as the bloodstream of the community, it connects everything."
Project Lyttelton also does other work, like teaching sustainability in schools - which the Tindall Foundation has backed financially - and Ms Jefferies said everything done through the project was done with love.
NZ Housing Foundation
Brian Donnelly is the executive director of the New Zealand Housing Foundation, which provides affordable housing for low income families in parts of New Zealand.
The Housing Foundation seeks to relieve poverty and build communities by enabling people who can't get state housing to get into homes through a range of co-ownership and tenure options.
Since it was founded in 2004, the charitable trust has provided affordable new homes for more than 300 families. It is currently involved in the 282-unit Waimahia Inlet housing project in South Auckland.
The Tindall Foundation has invested $4.3 million in it.
Mr Donnelly said it started in the early 2000s with a conversation with the Tindalls about the need for affordable housing.
"It was decided this foundation would be founded as an organisation that could make a difference in areas that needed it, like Auckland, Christchurch and Tauranga."
The original intent was to use Mr Donnelly's industry expertise to help other community housing groups but in about 2008, with the help of the Tindall Foundation, the Housing Foundation started taking on its own projects.
"We've been able to bring a lot of good people together, and they make us," Mr Donnelly said.