Net Zero-Energy Homes

Net Zero Energy House

Built: 2011

This net-zero energy home features insulated concrete forms, structural insulated panels, high-performance windows, cementitious siding and a solar photovoltaic system sized to cover all the energy usage. The main space is oriented to the north, with windows on other faces carefully regulated. This allows a lot of even daylight in the house without bringing in direct sun. The structural walls are made of "SIPs" (Structural Insulated Panels) - pre-fabricated, highly-insulated wall panels with no studs (saving energy and wood). The south-facing roof has a 13.4 kW photovoltaic array (solar panels). The combination of passive solar orientation, tight building envelope, and innovative technology to provide heating, cooling, and domestic hot water via one system minimizes the amount of energy required to heat the house.

Zero Cottage

Built: 2013

This project is an investigation of compact, sustainable urban development and a contemporary approach to living and working. Contrary to the name, Zero Cottage actually generates net positive 30% more energy than it uses. At just 712 square feet of living space over a 430 square foot workshop, every inch of the structure has been optimized for flexibility and efficiency. A 3 kW photovoltaic solar array cantilevers off the narrow roof structure and serves as a rain screen for the exterior metal side stair below. The Passive House construction combines a robust combination of exterior wall membrane layering, including continuous exterior foam insulation and triple-glazed windows. Heat generated from day-to-day use (by people, appliances, and computers) warms fresh air ventilated into the home. Likewise, the tight building envelope minimizes exterior heat gain on warmer days. With a 92% efficient heat-recovery ventilating (HRV) system, and an air-change-per-hour rating of 0.5, the house does not need conventional heating.

Seadrift Residence

Built: 2007

This sustainable, 1900-square-foot beach house design follows a rigorous sustainability program, achieving the Marin Planning Department's highest rating for resource efficiency. It is as environmentally friendly as it is stylish. The middle of the living space consists of a rotating fire orb that is designed to distribute warmth equally throughout the room. The generous amount of wood throughout the home gives a natural, inviting look while providing plenty of natural insulation. Photovoltaic panels generate all the home's electricity, sending surplus energy back to the grid. All the home's systems—hot water, HVAC, and radiant heating—are integrated, electric-based, and powered by the PV panels on the roof. The only use of natural gas is at the cooking range, which draws from a 50-gallon propane tank. With the exception of the propane tank, the home is net-zero in terms of its energy consumption.

Yin Yang House

Built: 2011

The Yin-Yang House is a net-zero energy single-family home. It was designed for a large and growing family, with an emphasis on the creation of public family spaces, an entertainment/social space, and a strong indoor-outdoor connection. Many of the materials used, including the bamboo interior, composite stone and tile countertops and bathroom finishes are recycled, and reinforce the environmental DNA of the house, which also has a green roof. Blown-in cellulose insulation, radiant heating and a host of other sustainable features aids in the performance of the building's heating and cooling. The active systems in the home include a 12 KW solar photovoltaic panel system, the largest such residential system available on the market. The solar panels also provide shade from the sun, preventing the house from becoming overheated.

Net Zero Laneway House

Built: 2012

Vancouver's first Net-Zero Solar Laneway House was built as an infill on an existing residential lot. The passive solar house is 1020 square feet and features 1' thick walls. The project was built using prefab Structural Insulated Panels (SIPs), has 95% LED lighting, a 500 gallon in-ground rainwater tank, drain-water heat recovery, a heat recovery ventilator, an air-source heat pump (for space heating and hot water), and an array of 12 solar panels on the roof. The solar energy system generates extra power in the summer - which is sold back onto the grid - and it draws on that stored power in the winter. The 18′ multi-fold doors on the living/dining space create a wide open indoor-outdoor connection while the door's southern orientation provides passive solar heating.