The Christchurch City Mission is opening the South Island's first supermarket-style self-serve foodbank.

It is part of an $11 million redevelopment completed over the past two years.

Missioner Corinne Haines said for some struggling people, shopping at big supermarkets could be intimidating.

The new foodbank - operational later this month - would run a bit like a supermarket, where clients could pick and choose items with support from staff.

Haines said it would help clients with practical skills to shop for healthy meals, with staff leading them through the process of choosing ingredients.

"I think people have been put off in the past because their parents didn't know how to shop and it was just easy to buy fast food, but also when you get to the counter and you can't afford to pay, that's a very embarrassing situation.

"Whereas here it's a points system and we can say: 'Oh, you're over, maybe you can put that one and that one back and you'll be right'."

Foodbank coordinator Steve Brinsden said it would change the way the City Mission gave out parcels.

"Because of the supermarket, we're thinking that we're going to reduce the number of parcels we need to give out by about 70 percent. So about 30 percent of the parcels will still have to remain because some people are always going to want the parcels, they're never going to be able to come to a supermarket and that's fine."

The redevelopment had been a four-year plan.

In October last year the Mission opened the first stage of it - an on-site cafe and transitional housing building. On Thursday, the Mission opened the last part with the new foodbank, as well as a warehouse area and offices.

Haines said the idea was to create a village atmosphere for clients, with the Mission being a one-stop shop. She said that way when a person came in, the Mission could offer them food, financial assistance and other help to get them back on track.

"We just pass them around our organisation, and being close and being in the same area is very helpful to channel people through our organisation and give them the total support that we can."

The foodbank was giving out about 350 boxes a week, and recently had to cut down the number because their food supply was low, she said.

"We used to give people six food parcels a year, I think we're down to five at the moment because we need to eke it out.

"Two years ago we didn't buy in much food - we had it all gifted. Now we're buying food every single month."

Winter was always the toughest month, and the demand for help was higher, Haines said.

"A lot of people are struggling financially… there's a lot of pressures on people, but especially in winter when electricity charges are really high."

Haines expected demand would get worse before it got better as winter had only just begun.

This story was originally published by RNZ.