"Bonfin", the property of the Fraternity Blanche Universelle, near Frejus (Provence), France, led by M. Ivanov. This modest two bedroom home was designed for a philosophical community dedicated to solar power in a local design idiom. Selected south facing lower and upper glazing was planned to heat the concrete slab and its rockbin below. Masonry walls and a central interior masonry wall were designed to provide over 90 percent passive heating and cooling.