SIPs (structural insulated panels)
Photographer: Colin Perry
Designer/Builder: Lanefab Design/Build
Certifications: EnerGuide 90 (see below)
Location: Vancouver, B.C., Canada
Size: 1,050 square feet (approximately 98 square metres)
Petto Chan and his wife, Billie Leung, spent many weekends looking at homes in Vancouver. They were living in his parents’ basement with their young daughter and wanted a place of their own. Their priorities included a home close to their work so they’d need only one car and office space for the many days Petto worked at home. Because she teaches baking in a high school, Billie craved a large kitchen, so she could use her baking skills at home for family and friends. Both she and Petto wanted a modern home that was small so they wouldn’t spend their time and money maintaining it.
Choosing a house
After looking at more than a hundred houses, the couple realized that they wouldn’t find what they wanted in terms of design or efficiency on their $800,000 budget in this area, where houses typically start at $1 million. One advantage of building a laneway house (see “Laneway houses: A brief history” below) was that all their money would go towards construction, rather than land. At that point, building in his parents’ backyard became a more attractive option. Not only could they build a house with the exact design they wanted, but they’d also still be able to enjoy his mom’s cooking on weekday evenings.
Before they applied for a permit or looked for a builder, they made sure they had a clear vision of what their laneway home would look like. First, it would be small but spacious. Instead of many small rooms they opted for fewer larger rooms. Instead of a formal dining room, they wanted a large kitchen where the three of them could eat at the kitchen island.
The house would also be very energy efficient. The 13-inch (or about 33 cm) thick walls include 6 and 1⁄2-inch (or approximately 17 cm) structural insulated panels (SIPs) and several inches of rock wool insulation in the inner service wall (which houses the wiring, plumbing, ducts and fire sprinkler piping). Photovoltaic (PV) panels on the roof provide all the energy required during the mildest months of the year, with only a small amount of additional energy needed for the colder months. The house is net zero energy for many months of the year, with monthly winter bills running about $80. Appliances are ENERGY STAR rated and lights are all LED.
Tracking the energy
The house’s performance continues to be monitored by Enlighten Manager, a tracking program from Enphase Energy®, that offers continuous data on the energy produced by the PV panels. After the first year and a half, the Solar Laneway House’s PV panels had produced 4.2 megawatt hours of power, saving the homeowners about $1,500 in energy costs.
Laneway houses: A brief history
Laneway houses are small-scale, fully independent homes that are typically built in the backyard of an existing single-family home. The houses often are located where a garage once stood, just off the rear alley, or lane, hence the name laneway. They were first approved in Vancouver, B.C., in 2009 thanks to the city’s EcoDensity policy.
Although they’ve been built in other Canadian cities, laneway houses are mostly found in Vancouver because it has such a large network of lanes. In 2009 when the law was enacted, about 59,000 houses were determined to be suited for laneway units. To date, the popular program has issued more than 1,600 permits. Extensive rules govern the size, shape and location of the houses. Other, more practical issues also fall within laneway regulations that oversee parking, the issuing of addresses (which could get complicated with two separate houses on the same lot), landscaping and sewer and water connections.
As a result of the laneway boom, the lane areas, which previously were often neglected, have become revitalized while providing expanded housing options for people who want to live in the city. Just as the city planned, this construction has added density to communities without construction of multistory apartment houses.
Laneway houses are a subcategory of accessory dwelling units (ADUs), which can also include basement dwellings, apartments over a garage and additional houses on an existing lot where a house already exists. Regulations for all of these units are specified by the state or province. In Vancouver, laneway houses must be sold with the original house but can be rented or occupied by family members.
The size of the house depends on the size of the lot, although the houses are typically between 500 square feet and 1,000 square feet (between 46 and 93 square metres). The maximum height for a laneway house is 20 feet (or 6 metres) and 1.5 storeys (which means the second floor has to be smaller than the ground floor to reduce the apparent size of the structure).
Laneway houses (and other ADUs) offer an alternative type of housing for people who don’t want to live in an apartment building but either can’t afford or don’t need a full-size single-family house. For additional information about laneway houses in Vancouver, visit the city’s website.
Green features of the Chan-Leung solar laneway house
- Locally sourced cedar siding, windows and panels
- Dual-flush toilets
- Low-flow faucets and showers
- Low/no-VOC paint and adhesives
Energy efficient features
- PV panels
- Triple-pane windows and doors
- High-efficiency heat pump
- Drain water heat recovery system
- Heat pump hot water tank
- EPS foam
- LED lighting
- ENERGY STAR–rated appliances
Advantages of drain water heat recovery
In most houses a great deal of energy is lost when the warm water from showering goes down the drain. According to Energy Saver, “Water heating is the second largest energy expense in your home. It typically accounts for about 18 percent of your utility bill after heating and cooling.”
A drain water heat recovery system captures heat from grey water (usually from the shower) and uses it to supplement the water heater, cutting down on energy required to obtain hot water. The recovered heat also expands the amount of hot water available in the home so that the last person showering won’t run out of hot water. The house then consumes less energy, so energy bills decrease. For further information about the system used in the Solar Laneway House, visit the Watercycles™ website.
The Canadian EnerGuide rating measures a home’s energy performance so that current and future owners will know fairly precisely how energy efficient the structure is. An approved EnerGuide adviser certifies the energy performance rating.
The home’s energy efficiency level is rated on a scale of 0 to 100. An uninsulated house with significant air leaks would have a rating of 0 and a high energy consumption. A typical new home in Vancouver is built to an EnerGuide 76 rating. The Solar Laneway House has an energy rating of 90, which means it’s energy efficient. Houses with a rating of 91 to 100 are often off the grid. For additional information about this program, visit the Natural Resources Canada website.
Sheri Koones is an award-winning author and a recognized authority on home construction. She’s the author of six books on prefabricated residential construction and a freelance writer and speaker.
Credits for the Solar Laneway House: Designer/builder: Lanefab Design/Build; Photographer: Colin Perry; Text: Sheri Koones; Floor plan: Chuck Lockhart. Book: Prefabulous Small Houses, © 2016 The Taunton Press.