MONTPELLIER, France — “It looks like a toothbrush. It’s quite strange,” said the Japanese architect Sou Fujimoto. He was speaking about his first project in France, a mixed-use residential tower in Montpellier where, thanks to 300 days of sunshine annually, outdoor living is part of the lifestyle.

Inspired by a tree, L’Arbre Blanc, or the White Tree, features a facade bristling with cantilevered pergolas and balconies up to nearly 25 feet , or 7.5 meters, long.

“When we understood the basic conditions of the lifestyle,” Mr. Fujimoto said, “we understood outdoor terraces are simply a must.”

The unusually shaped tower, with 113 apartments, a restaurant, an art gallery and a rooftop bar, won a competition sponsored by Montpellier’s City Council in 2013. The competition required a team of a young architect and a more experienced one.