Hundreds of volunteers are working hard in the heat this week for Habitat for Humanity.

As part of a 150-home build nationwide through the Jimmy and Rosalynn Carter Work Project, 20 homes are being built this week at a site in Winnipeg's St. James area. Homes are also being built in Brandon and Portage.

Habitat for Humanity Manitoba CEO Sandy Hopkins says they will have 500 people on site (in St. James) every day, 400 building and 100 in support roles. He says in total this week there will be about 1,600 individuals on site working.

One of them is Orly Friesen, a volunteer who says he's been involved with Habitat on and off for more than 10 years. He says Habitat is a good organization with good people doing good things, though he's not a fan of the temperatures they're working in.

"The weather is not to my liking at all, it's much too hot and humid and I don't much care for it, but we all carry on," says Friesen, who was part of a faith build last year in which nine churches in the St. Vital area got together to build a home.

Hopkins says they're keeping everybody hydrated, and they have full medical staff on site.

Hopkins calls this their blitz build, something he says they've done in eight of the 11 years he's been with Habitat. At 20 homes in a week, he says this one's the biggest he's been a part of.

"We are simulaneously building 20 homes. Fifteen of those homes will remain here on permanent foundations, five of them are being built on what we call RTMs, ready-to-move," says Hopkins.

Former US president Jimmy Carter and his wife Rosalynn will be visiting Winnipeg on Thursday.