The ambition of this project was to turn an existing 13,025 sf energy hog into a zero-energy residence. 11,000 sf of solar panels, a solar water heater and a series of other measures now contribute to a much reduced monthly energy bill. At the same time, spaces and their relation to the landscape were radically transformed by the new terrace with an almost invisible glass railing, sliding doors that retract completely into pockets and new custom skylights which triangular shaped purloins nearly vanish.