By Jody McCutcheon
Knowing you’re doing your part to tread lightly on our planet is a good feeling, so we try to do this in different ways, be it recycling, riding a bike to work, or cutting down on our overall consumption. Another – perhaps more important – way of minimizing our eco-footprint is by living in zero energy homes.
Traditional buildings consume four tenths of all the fossil fuel energy in the US and EU, while contributing significantly to greenhouse gas emissions. On the other hand, zero energy homes (a.k.a. net-zero energy buildings, or NZEBs) have greatly reduced their carbon emissions and reliance on fossil fuels in various ways. The total amount of energy consumed annually by a NZEB roughly equals the renewable energy it creates, commonly via solar panels and wind turbines. Such buildings may also reduce their reliance on grid energy by using high-efficiency heating, ventilation, air conditioning (a.k.a. HVAC) and lighting systems.
As the cost of alternative energy technologies shrinks and that of fossil fuels rises, NZEBs are becoming more practical – and fashionable. Below are five very different dwellings that share a common net-zero theme, as well as beautiful design.
1. House of Shifting Sands
A point where water meets land is a nice starting point. Nestled amidst miles of undeveloped Cape Cod National Seashore is the House of Shifting Sands. Serving equally well as a year-round cottage or a retreat for those seeking peaceful contemplation or ceaseless creative vibes, the award-winning, net-zero energy beach house designed by Ruhl Walker Architects “fit its fragile site seamlessly.” What better way to symbolize this than an entrance surrounded by dense foliage? (which will be the case when the planted flora around the door matures).
A large living/dining space is complemented by glass walls that permit stunning ocean views and refreshing sea breezes. A quirky “hole” opens in the middle of the house for natural ventilation via floor-to-ceiling awning windows, with a flower-lined trellis wafting floral scents through the interior. An attached studio and yoga loft makes for an ideal workshop or meditative space. Other interesting and rather luxurious features include hot tubs, outdoor showers, a small hill-top shed equipped with running water and an espresso machine, a half basketball court dug into the hill, hammocks and fire pits.
The House of Shifting Sands produces its own energy with a 10kW rooftop solar photovoltaic array on both main house and studio, super high efficiency air-to-air heat exchangers and energy recovery ventilators. While the residence hasn’t been LEED certified, it has certainly been designed with such certification in mind. (All images: Jane Messinger)
2. Murphy Dunn Net Zero House
Moving down the east coast a bit, we come to the Murphy Dunn Net Zero House. It was designed by Chapel Hill, N.C., architect Arielle Condoret Schechter for her favourite builder, Kevin Murphy of Newphire Building, and his family of four. The 2,950 square-foot residence is located on a secluded, 4.3-acre site adjacent to a creek and conservancy land. The indoor-outdoor synergy is enhanced by a screened porch as well as the private interior courtyard that typifies Schechter’s residential work.
The dwelling design combines modern architecture’s flat rooflines, simple volumes and open floorplans with acute environmental sensitivity: the Murphy Dunn House has proved to be net positive, as the 7.9kW solar array offers about thirty dollars of excess energy per month. Murphy intends to put this excess power into an electric car. Furthermore, the residence boasts an excellent HERS (Home Energy Rating Score) of -3, and its green status has been third-party verified with a National Green Building Standard “Gold” rating. That’s an impressive list of attributes for a cost of $227 per square foot.
3. Lodgepole Retreat
Just imagine skiing in the Rockies, and then returning to your cozy chalet-style cabin, which happens to be a NZEB. Welcome to Lodgepole Retreat, a 2,500 square-foot, three-bedroom, three-bathroom cabin, the People’s Choice Award winner in the 2013 Design Awards and conceived by Colorado architecture firm Arch11.
Situated 9,000 feet above sea level among a lodgepole pine forest and a sensitive wetland ecosystem, Lodgepole Retreat borrows its architectural simplicity from the region’s traditional mining and mill structures. The flat, angled roof is a hat-tip to traditional chalet architecture, while functionally allowing heavy snowfall to slide right off. The fire-resistant exterior’s mottled finish blends well with the color of the tree trunks populating the surrounding forest.
A raised concrete plinth and glazed, floor-to-ceiling windows allow for wide-angled views of rugged mountain ridge and alpine meadow, with the interior boasting a harmonious blend of polished concrete floors, crisp, white surfaces and wood fittings. A wood-burning fireplace warms an open-concept living space. It also helps the cabin achieve its net-zero energy performance, as do the 10kW rooftop photovoltaic system, LED lighting system, electric boiler and an air-to-air heat exchanger.
4. Avava Britespace
This next NZEB can be anywhere we want it to be, because it’s essentially a DIY home. And how about two sustainability concepts for the price of one? San Francisco-based company Avava has created a tiny, modular net-zero energy home, the Britespace. The prefab dwelling is delivered in flat-packed boxes, Ikea-esque, and can be constructed in only six weeks. (Most pre-fab homes take from ten to fifty (!) weeks to assemble.)
Having first appeared at the 2006 Burning Man festival, the Britespace now offers three options: Model 264, Model 352 and Model 480, with each model number representing the square footage. Model 480 is a one-bedroom home replete with kitchen, bedroom, living area and closet.
Designed net-zero-ready, each home can accommodate an electric water heater, a graywater collection system and a rooftop solar array with Tesla battery packs that store generated energy. The interior is adorned with LED lighting, oak flooring and high ceilings that make the tiny house look huge, and they’re low-VOC (volatile organic compounds) and formaldehyde-free. The many windows provide plenty of natural light, and you can add your own person touches, with customizable finishes, window and trim colours, cabinets, counters and flooring.
With a base price ranging from $117,000 to $223,000, this tiny home ain’t cheap. But every dollar works hard for both you and the planet. (All images: Sasha Blackshear)
5. Brandywine House
What better place to showcase a net-zero energy building than the US capital? Designed by Robert M. Gurney Architect, Brandywine House stands like a monument in northwest Washington, DC, a quick jaunt from Connecticut Avenue’s shops and restaurants, and close to Rock Creek Park.
The interior is light-filled and additionally warmed by wood accents, including forest-certified or reclaimed white oak, mahogany, rosewood and various zebra woods. Add in the limestone and various granites, and the interior boasts a “rich material palette.”
Brandywine’s net-zero energy efficiency comes from a geothermal HVAC system with hydronic heating, solar hot water tubes and photovoltaic panels. And with plenty of windows and skylights, daylight is liberally exploited, while solar gain is modulated with computer-programmed shading devices.
(All images: Anice Hoachlander).