This Boulder, Colorado remodel by fuentesdesign demonstrates the possibility of renewal in American suburbs, and Passive House design principles. Once an inefficient single story 1,000 square-foot ranch house with a forced air furnace, has been transformed into a two-story, solar powered 2500 square-foot three bedroom home ready for the next generation. The new design for the home is modern with a sustainable theme, incorporating a palette of natural materials including; reclaimed wood finishes, FSC-certified pine Zola windows and doors, and natural earth and lime plasters that soften the interior and crisp contemporary exterior with a flavor of the west. A Ninety-percent efficient energy recovery fresh air ventilation system provides constant filtered fresh air to every room. The existing interior brick was removed and replaced with insulation. The remaining heating and cooling loads are easily met with the highest degree of comfort via a mini-split heat pump, the peak heat load has been cut by a factor of 4, despite the house doubling in size. During the coldest part of the Colorado winter, a wood stove for ambiance and low carbon back up heat creates a special place in both the living and kitchen area, and upstairs loft. This ultra energy efficient home relies on extremely high levels of insulation, air-tight detailing and construction, and the implementation of high performance, custom made European windows and doors by Zola Windows. Zola’s ThermoPlus Clad line, which boasts R-11 triple glazing and is thermally broken with a layer of patented German Purenit®, was selected for the project. These windows also provide a seamless indoor/outdoor connection, with 9′ wide folding doors from the dining area and a matching 9′ wide custom countertop folding window that opens the kitchen up to a grassy court where mature trees provide shade and extend the living space during the summer months. With air-tight construction, this home meets the Passive House Retrofit (EnerPHit) air-tightness standard of